Mathematics Tutor Singapore | JC H2 Maths Maclaurin series can seem like a wall of derivatives, factorials and familiar functions. But the fundamental idea is accessible: near x=0, a complicated function can be represented approximately by a polynomial whose coefficients are chosen so that its value and successive derivatives match the original function at zero.
Did you know that sin x is approximately x for small x only when the angle is expressed in radians? That condition matters. Substituting five as though it were a small radian angle merely because five degrees is small is not a valid use of the approximation. Understanding the domain, variable and requested precision is as important as remembering an expansion.
This H2 Mathematics 9758 tutorial develops Maclaurin series from repeated differentiation, then explains eˣ, sine, cosine, logarithmic and rational-binomial expansions, products of series, small-angle estimates, implicit examples and appropriate restrictions. The 2026 SEAB syllabus includes these methods and explicitly excludes derivation of the general term of a series.
Parents seeking structured learning support can arrange an eduKate Singapore parent–student consultation. The original eduKateSG premium small-group teaching model uses three pupils in a group with 1.5-hour weekly lessons, focusing on first principles, careful working, correction and independent transfer rather than claiming a guaranteed A-Level grade.
Browse JC H2 Maclaurin series and approximation chapters
- 1. Maclaurin Series Describe a Function Near Zero
- 2. How Repeated Derivatives Determine Coefficients
- 3. The Meaning of Factorials and the Constant Term
- 4. Standard Expansion of eˣ
- 5. Standard Expansions of sin x and cos x
- 6. A Small Angle Must Be Measured in Radians
- 7. A Closer Look at sin 0.2 and cos 0.1
- 8. The Natural Logarithm Series ln(1+x)
- 9. The Generalised Binomial Expansion
- 10. Worked Expansion of √(1+x)
- 11. Expansion of 1/(1−x) and 1/(1+x)
- 12. Derive a New Series from Two Standard Series
- 13. Worked Product: eˣ cos 2x
- 14. Worked Product: eˣ sin x
- 15. Subtract Logarithmic Series to Simplify
- 16. Repeated Differentiation of a New Function
- 17. Implicit Differentiation and First Few Terms
- 18. Why Approximation Error Matters
- 19. Convergence Intervals and Domain Restrictions
- 20. Select the Requested Order or Nonzero Terms
- 21. A Graphing Calculator Is a Check, Not the Derivation
- 22. Ten Mistakes an H2 Maths Tutor Should Diagnose
- 23. Twenty-Four Original Maclaurin Practice Questions
- 24. A Ten-Session JC1 to JC2 Study Programme
- 25. Why This Matters for Mathematics Beyond A-Levels
- 26. Frequently Asked Parent and Student Questions
- 27. Official 2026 SEAB Syllabus and Further Learning
Maclaurin Series Describe a Function Near Zero
Suppose a function f is sufficiently differentiable near zero. A polynomial that matches f(0), f′(0), f″(0) and further derivatives can model its local behaviour. The Maclaurin series is the Taylor expansion centred at zero.
Its familiar form begins f(x)=f(0)+f′(0)x+f″(0)x²/2!+f‴(0)x³/3!+…, in a region where the corresponding series converges to the function. A truncated polynomial may approximate f even when we use only the first few terms.
The centre matters. A Maclaurin expansion is designed around x=0. Using a low-order polynomial far from zero may produce a poor approximation even for a function with a well-defined Maclaurin series.
| Polynomial term | Coefficient | What it matches |
|---|---|---|
| Constant | f(0) | Value at zero |
| x term | f′(0) | First derivative at zero |
| x² term | f″(0)/2! | Second derivative |
| x³ term | f‴(0)/3! | Third derivative |
How Repeated Derivatives Determine Coefficients
For a function f(x)=ln(1+x), where x is near zero and greater than −1, evaluate derivatives at zero. We have f(0)=0; f′(x)=1/(1+x), so f′(0)=1. Then f″(x)=−1/(1+x)², giving f″(0)=−1.
The third derivative is f‴(x)=2/(1+x)³, so f‴(0)=2. The cubic Maclaurin approximation is therefore x−x²/2+x³/3, because the x³ coefficient is 2/3!=2/6=1/3.
This method illustrates why the second coefficient is not simply f″(0) and the third is not simply f‴(0). Factorials account for the derivatives of powers: the second derivative of x² is two; the third derivative of x³ is six.
The Meaning of Factorials and the Constant Term
The factorial n! is the product n×(n−1)×…×1 for positive integers n, while 0!=1. Hence 2!=2, 3!=6 and 4!=24. These denominators arise naturally when differentiating polynomial powers repeatedly.
| n | n! | Coefficient form |
|---|---|---|
| 0 | 1 | f(0)/0! |
| 1 | 1 | f′(0)/1! |
| 2 | 2 | f″(0)/2! |
| 3 | 6 | f‴(0)/3! |
| 4 | 24 | f⁽⁴⁾(0)/4! |
If a learner writes f″(0)x² instead of f″(0)x²/2!, their proposed polynomial has second derivative 2f″(0) at zero and therefore fails the matching condition. I teach the factorial through this derivative check.
Standard Expansion of eˣ
For f(x)=eˣ, every derivative is again eˣ. At zero, every derivative equals one. Thus eˣ=1+x+x²/2!+x³/3!+x⁴/4!+…, and this series converges for all real x.
At x=0.1, keep terms through x³: 1+0.1+0.1²/2+0.1³/6=1.105166666…. The actual e⁰·¹ is about 1.105170918, so the cubic approximation is close but not exact.
| Term kept | Approximation for e⁰·¹ |
|---|---|
| 1+x | 1.1 |
| 1+x+x²/2 | 1.105 |
| Through x³/6 | 1.1051666667 |
| Function value | ≈1.1051709181 |
This calculation is a model of precision: the power-series coefficient comes from the function, while the error depends on both how many terms we retain and the value of x.
Standard Expansions of sin x and cos x
The standard sine expansion in radians is sin x=x−x³/3!+x⁵/5!−…, while cosine is cos x=1−x²/2!+x⁴/4!−… . Sine uses odd powers because it is an odd function; cosine uses even powers because it is even.
There is no constant term in the sine expansion because sin0=0. Cosine has constant one because cos0=1. The alternating signs follow the derivatives of sine and cosine cycling through cosine, negative sine, negative cosine and sine.
| Function | First nonzero terms | First omitted power after shown terms |
|---|---|---|
| sin x | x−x³/6+x⁵/120 | x⁷ |
| cos x | 1−x²/2+x⁴/24 | x⁶ |
| eˣ | 1+x+x²/2+x³/6 | x⁴ |
A common transcription error is to write sin x≈x−x²/2. This is a cosine-type even-power term, not the first sine correction. Evaluating derivatives at zero can detect the mistake.
A Small Angle Must Be Measured in Radians
Small-angle approximations include sin x≈x, cos x≈1−x²/2 and tan x≈x for suitably small x in radians. The stated unit is essential because derivatives of standard trigonometric functions take their familiar forms with radian arguments.
Five degrees is about π/36≈0.08727 radians. Thus sin5° is approximately 0.08727 under the first-order small-angle approximation, not approximately five. The exact sine value is about 0.08716, demonstrating the scale.
A student who enters a radian approximation into a calculator set to degrees may obtain an incompatible comparison and mistakenly blame the Maclaurin method. Always label the units and check the calculator’s angle mode.
A Closer Look at sin 0.2 and cos 0.1
For sin0.2 with x measured in radians, the cubic approximation is x−x³/6=0.2−0.008/6=0.198666666…. The actual sine is approximately 0.198669331, a difference of only a few millionths.
For cos0.1, the quadratic approximation 1−x²/2=1−0.005=0.995. The actual cosine is about 0.995004165. Both approximations are plausible because the next neglected terms contain higher powers of a small number.
| Quantity | Approximation | Function value |
|---|---|---|
| sin0.2 | 0.2−0.2³/6≈0.198666667 | ≈0.198669331 |
| cos0.1 | 1−0.1²/2=0.995 | ≈0.995004165 |
| tan0.1 | First order ≈0.1 | ≈0.100334672 |
For x nearer one or larger, a short polynomial may require more terms or a different expansion centre for good accuracy. The phrase ‘small angle’ must be interpreted mathematically rather than treated as permission to substitute any value.
The Natural Logarithm Series ln(1+x)
The standard series ln(1+x)=x−x²/2+x³/3−x⁴/4+… converges for −1 At x=0.2, the first three nonzero terms give 0.2−0.04/2+0.008/3≈0.182666667. The actual ln1.2 is approximately 0.182321557. The next term −0.2⁴/4 is negative, moving the partial sum down towards the exact value. A student should not use the real logarithmic series at x=−1 because ln(1−1)=ln0 is undefined and the standard series diverges there. Convergence and function domain both matter. For a rational exponent n, the generalised binomial expansion begins (1+x)ⁿ=1+nx+n(n−1)x²/2!+n(n−1)(n−2)x³/3!+…, within its appropriate domain. If n is a nonnegative integer, the expansion terminates after finitely many terms and defines a polynomial for all real x. For non-integer rational n or negative integer n, the resulting infinite series is valid at least for |x|<1, with endpoints requiring separate care. The 2026 H2 syllabus expects the first few terms and use of standard series, but explicitly excludes deriving the general term of a series as a problem requirement. Focus on the specified coefficient techniques and interpretations. For f(x)=√(1+x)=(1+x)^(1/2), substitute n=1/2 into the binomial coefficients. The linear coefficient is 1/2. The quadratic coefficient is (1/2)(−1/2)/2=−1/8. The cubic coefficient is (1/2)(−1/2)(−3/2)/6=1/16. Thus √(1+x)≈1+x/2−x²/8+x³/16 for small |x|. At x=0.1, the cubic approximation gives 1+0.05−0.00125+0.0000625=1.0488125, close to √1.1≈1.048808848. Substituting x=3 into that short approximation would be inappropriate even though the real square root √4 exists: the non-integer binomial power series about zero is being used outside its radius of convergence. The geometric series gives 1/(1−x)=1+x+x²+x³+… for |x|<1. Replacing x by −x yields 1/(1+x)=1−x+x²−x³+..., again for |x|<1. At x=0.1, 1/(1+0.1)=0.9090909… . The cubic partial sum 1−0.1+0.01−0.001=0.909 is close. More terms continue to refine the value. This is a useful bridge from JC geometric progressions. An infinite sum formula and a Maclaurin expansion are related, but the condition |x|<1 must be retained when interpreting the series as a convergent equality. Once a student knows standard expansions, a product such as eˣcos2x can be approximated by multiplying truncated series and collecting like powers. We only need to keep terms that could contribute to the requested order. If the question asks through x³, any term already of order x⁴ or higher can be omitted from the final cubic expression, provided we do not discard a lower-order contribution during multiplication. I recommend writing the source expansions on separate lines, showing each term with its power. A student who expands only the first bracket term may miss cross products that alter the x² or x³ coefficients. Use eˣ=1+x+x²/2+x³/6+… and cos2x=1−2x²+… . Multiply: (1+x+x²/2+x³/6)(1−2x²) to the order required. The constant term is one and the x term is x. The x² coefficient is 1/2−2=−3/2. The x³ coefficient is 1/6−2=−11/6, because x multiplied by −2x² contributes −2x³. The result can be checked by differentiating eˣcos2x repeatedly at zero, although the product-of-standard-series route is usually shorter here. Both methods must agree on the coefficients. Similarly, expand eˣsin x to cubic order. The sine series is sin x=x−x³/6+…, and the exponential is 1+x+x²/2+x³/6+… . Multiplying gives x+x²+[x³/2−x³/6]+…, so the result is x+x²+x³/3+… . Notice that the product has no constant term because sine begins with x. A student who includes the sine series’ x⁵ term while computing only a cubic expansion wastes time but does not help accuracy at that requested order. Efficient series work is largely careful power accounting. Use ln((1+x)/(1−x))=ln(1+x)−ln(1−x). The first standard series begins x−x²/2+x³/3−x⁴/4+…, while ln(1−x) begins −x−x²/2−x³/3−x⁴/4−… for |x|<1. Subtract the second series. The even-power terms cancel and the odd terms double, giving ln((1+x)/(1−x))=2x+2x³/3+2x⁵/5+…, valid for |x|<1. This result also makes sense through symmetry: replacing x by −x reverses the ratio and changes the sign of its logarithm, so the function is odd. Its Maclaurin series should therefore contain only odd powers. Consider f(x)=1/(1−x). By differentiation, f(0)=1, f′(x)=1/(1−x)² so f′(0)=1, f″(x)=2/(1−x)³ so f″(0)=2, and f‴(x)=6/(1−x)⁴ so f‴(0)=6. Substitute into the cubic Maclaurin polynomial: 1+x+(2/2!)x²+(6/3!)x³=1+x+x²+x³. This agrees with the standard geometric expansion. We have deliberately computed only the first few derivatives. Deriving an all-n general-term formula is outside the 2026 syllabus’s required Maclaurin problem scope; checking finite coefficients is the relevant skill. Let y be an implicitly defined differentiable function near zero satisfying y+y²=x, with the branch y(0)=0. Differentiate with respect to x: (1+2y)y′=1. At x=0, y=0, so y′(0)=1. Differentiate again: (1+2y)y″+2(y′)²=0. At zero this gives y″(0)=−2. Differentiate a third time to obtain (1+2y)y‴+6y′y″=0. At zero, y‴(0)=12. This example illustrates the repeated implicit differentiation listed in the H2 syllabus. A student who forgets y′ when differentiating y² is treating the dependent variable as a constant instead of a function of x. A finite Maclaurin polynomial is an approximation, not automatically an exact equality to the original function. Its accuracy depends on the omitted terms, the value of x and the interval in which the expansion is valid. For ln(1.2) with x=0.2, the cubic approximation 0.182666667 is above the true value about 0.182321557; the next negative quartic term makes the approximation smaller. In this alternating case the signs give useful intuition about how partial sums approach the result. The direction of error is not universally guaranteed simply from the word Maclaurin. A student should use the known series pattern, valid remainder bounds when provided and numerical checks where appropriate. The exponential, sine and cosine series converge for all real x. The binomial series for a rational non-integer exponent can be used directly in the standard form within |x|<1, and logarithm ln(1+x) has a different endpoint behaviour. For composed functions, the inner expression must also satisfy the appropriate restriction. For instance, expanding √(1+4x) by the standard binomial series requires |4x|<1 for a guaranteed local power series, so |x|<1/4. Examination wording may request terms up to and including x³, the first three nonzero terms or a polynomial approximation of a particular order. Those are different instructions. The first three nonzero terms of cos x are 1, −x²/2 and x⁴/24, not 1 plus an x term plus an x² term. The x and x³ coefficients are zero and should not be counted as nonzero terms. The first three nonzero terms of sin x are x, −x³/6 and x⁵/120. If a question instead requests through x³, only the first two nonzero terms appear. I ask the student to underline the exact stopping instruction before differentiating or multiplying. A graphing calculator can compare a polynomial approximation with the original function, especially near zero. For instance, plotting sin x and x−x³/6 over a small interval shows the two curves nearly overlapping. But the calculator cannot replace showing which derivatives or standard expansions produced a requested coefficient. Nor should its decimal output replace an exact radical or rational coefficient when the question asks for exact series terms. A useful final check is to substitute x=0: the polynomial must return f(0). Then compare its derivative at zero if needed. These tests reveal missing constant or linear terms quickly. Two students may both obtain an incorrect cubic approximation, but one forgot a factorial while the other omitted a cross-product in series multiplication. A targeted tutorial should not prescribe the same worksheet to both learners. f(0)=1, so expansion begins 1. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. f′(0)=1, giving +x. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1+x+x²/2+x³/6. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. x−x³/6+x⁵/120. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1−x²/2+x⁴/24. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 0.2−0.2³/6≈0.198666667. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1−0.1²/2=0.995. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 5°=π/36 radians; sin5°≈π/36 at first order. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. x−x²/2+x³/3. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1+x+x² for |x|<1. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1−x+x²−x³ for |x|<1. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. √(1+x)=1+x/2−x²/8+x³/16+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1.0488125 through cubic order. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1−x/2+3x²/8−5x³/16+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1−2x²+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 3x−(9/2)x³+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1+x−3x²/2+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. 1+x−3x²/2−11x³/6+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. x+x²+x³/3+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. ln((1+x)/(1−x))=2x+2x³/3+… for |x|<1. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. For branch y(0)=0, y=x−x²+2x³+… . State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. f″(0)=−1, so x² coefficient −1/2. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. For √(1+4x), require |x|<1/4 when using the standard binomial series. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. Count powers 0,2,4; do not count zero coefficients. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. At x=0.1, cubic eˣ approximation ≈1.105166667, actual ≈1.105170918. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. The coefficient of x² in eˣcos2x is 1/2−2=−3/2. State the standard expansion or evaluated derivative used, keep only terms of the requested order and check any composition’s convergence condition. Where a decimal estimate is requested, use radian mode for trigonometric functions. Students should compare an exact expansion with a numerical approximation, then explain why keeping another term changes precision. That is more informative than memorising twenty formulas without knowing when to apply them. Maclaurin series are a foundation for numerical methods and approximations used in Physics, Economics, Engineering and scientific computing. Approximating a function by polynomials can simplify calculations when a direct formula is inconvenient or when only a small local change matters. At university, students learn more general Taylor series, error bounds, convergence theory and numerical algorithms. H2 Mathematics builds the necessary intuition by matching derivatives, using known series and controlling the approximation’s domain. These skills support quantitative pathways, but no single topic or tutorial guarantees examination outcomes or university admission. Students should verify programme requirements separately from mathematics revision. A Taylor expansion centred at x=0 that uses derivatives at zero to determine polynomial coefficients. The n-th derivative of xⁿ is n!, so dividing by n! matches the desired derivative at zero. Its finite truncation is a polynomial approximation; the full series may represent the function under convergence conditions. The standard derivatives of trigonometric functions and the corresponding expansions assume radian arguments. x−x³/6+x⁵/120. 1−x²/2+x⁴/24. No. ln(1+x) is undefined at x=−1 and the corresponding series diverges. Multiply terms and collect powers, retaining only contributions up to the requested order. It combines +x²/2 from eˣ and −2x² from cos2x, giving −3x²/2. Omit zero coefficients when counting the terms and keep the first three that are actually nonzero. The 2026 syllabus expressly excludes derivation of the general term of a series. No. It can check numerical accuracy but not substitute for the required coefficient method. Follow the official year-specific syllabus; secure standard series and finite coefficients before university extensions. The SEAB 2026 H2 Mathematics 9758 syllabus index and official H2 Mathematics 9758 2026 specification list Maclaurin series in section 5.2, including rational binomial, eˣ, sin x, cos x, ln(1+x), repeated and implicit differentiation, products of standard series, convergence ranges and small-angle approximations. They exclude questions requiring derivation of the general term. Continue through the Mathematics Learning Hub, How Mathematics Works and the eduKate Mathematics Learning System. For preparation, see JC H2 Calculus Applications, JC H2 Geometric Progressions and Series and JC H2 Graphing Calculator and Exact Answers. For the trigonometric prerequisite read JC H2 Trigonometric Identities and Equations. For exam-wide organisation use JC H2 Mixed-Paper Method Selection. The original Secondary 1 Mathematics Tutor Clementi reference is immutable and has not been edited. Bring one correctly written standard expansion and another Maclaurin example where a derivative coefficient, crossed term or domain condition was missed. Targeted feedback can identify whether to rebuild calculus, trigonometry, algebraic manipulation or series interpretation. Contact eduKate Singapore · eduKateSG Facebook · WhatsApp H2 Maths enquiryThe Generalised Binomial Expansion
Exponent n First terms Simple domain note 2 1+2x+x² Polynomial, all real x −1 1−x+x²−x³+… |x|<1 1/2 1+x/2−x²/8+x³/16+… |x|<1 −1/2 1−x/2+3x²/8−5x³/16+… |x|<1 Worked Expansion of √(1+x)
Term Coefficient Contribution at x=0.1 Constant 1 1 x 1/2 +0.05 x² −1/8 −0.00125 x³ 1/16 +0.0000625 Total through x³ 1.0488125 Expansion of 1/(1−x) and 1/(1+x)
Derive a New Series from Two Standard Series
Worked Product: eˣ cos 2x
Power Contributions Coefficient x⁰ 1×1 1 x¹ x×1 1 x² x²/2−2x² −3/2 x³ x³/6−2x³ −11/6 Worked Product: eˣ sin x
Subtract Logarithmic Series to Simplify
Repeated Differentiation of a New Function
Implicit Differentiation and First Few Terms
Quantity at zero Value Series contribution y(0) 0 No constant y′(0) 1 +x y″(0) −2 −x² y‴(0) 12 +2x³ Why Approximation Error Matters
Convergence Intervals and Domain Restrictions
Series Convenient validity statement eˣ, sin x, cos x All real x 1/(1−x) geometric series |x|<1 ln(1+x) standard series −1 (1+x)¹ᐟ² binomial series |x|<1 for standard local expansion (1+x)ⁿ for nonnegative integer n Finite polynomial, all real x Select the Requested Order or Nonzero Terms
A Graphing Calculator Is a Check, Not the Derivation
Ten Mistakes an H2 Maths Tutor Should Diagnose
First wrong move Likely misconception Next teaching question Uses five degrees as x=5 in sin x≈x Radian condition missed Convert 5° to radians Writes sin x≈x−x²/2 Parity and derivative pattern wrong What is f″(0)? Omits factorial in x³ term Derivative matching incomplete What is the third derivative of x³? Uses ln(1+x) series at x=−1 Domain/convergence ignored Is ln0 defined? Uses √(1+4x) expansion for x=1 Inner argument outside local radius What is |4x|? Multiplies series but misses x×(−2x²) Cross-product omitted Which terms contribute to x³? Reports first three cos terms as 1,0x,−x²/2 Nonzero wording misread Is 0x a nonzero term? Cancels only one of the even ln terms Parity overlooked What is f(−x)? Treats truncated approximation as exact for all x Meaning of approximation lost What higher terms were omitted? Differentiates y² as 2y in an implicit relation Chain rule omitted Is y a function of x? Twenty-Four Original Maclaurin Practice Questions
1. Constant term of eˣ
2. Linear term of eˣ
3. First four eˣ terms
4. First three nonzero sin terms
5. First three nonzero cos terms
6. sin0.2 cubic estimate
7. cos0.1 quadratic estimate
8. Small-angle unit
9. First three ln(1+x) nonzero terms
10. First three 1/(1−x) terms
11. First four 1/(1+x) terms
12. Binomial sqrt expansion
13. sqrt approximation at x=0.1
14. Binomial (1+x)^(−1/2)
15. Expand cos2x to x²
16. Expand sin3x to x³
17. Product eˣcos2x to quadratic
18. Product eˣcos2x to cubic
19. Product eˣsin x to cubic
20. Log ratio through cubic
21. Implicit y+y²=x
22. Second derivative at zero for cos x
23. Local convergence restriction
24. First three nonzero terms of cos x
25. Compare approximation
26. Difference between moments of series
A Ten-Session JC1 to JC2 Study Programme
Session Skill Independent check 1 Meaning of Maclaurin centre and derivatives Matches f(0) 2 Factorials and x²/x³ coefficients Uses correct denominators 3 Standard exponential and trigonometric series Writes signs and powers 4 Small-angle radians and error Uses correct unit 5 Logarithm and binomial series Checks domain 6 Expanding a composed function Keeps inner argument 7 Multiplying two standard series Collects powers accurately 8 Repeated differentiation Finds first coefficients 9 Implicit differentiation example Includes y′ correctly 10 Mixed delayed H2 question Respects terms and restrictions Why This Matters for Mathematics Beyond A-Levels
Frequently Asked Parent and Student Questions
What is a Maclaurin series?
Why do factorials appear?
Is Maclaurin the same as an ordinary polynomial?
Why must small angles be in radians?
What are the first three nonzero sine terms?
What are the first three nonzero cosine terms?
Does the logarithm series work at x=−1?
How can two standard series be multiplied?
Why is eˣcos2x’s x² coefficient negative?
What does a first-three-nonzero-terms request mean?
Is deriving the general term examined in H2 9758?
Can a graphing calculator replace the derivation?
Should every H2 learner attempt advanced error bounds?
Official 2026 SEAB Syllabus and Further Learning
Arrange a Parent–Student Consultation
