Secondary 3 G2 Mathematics Tutor Bukit Timah | Algebraic Fractions: Simplification Checks. Did you know? Cancelling a factor is valid, but cancelling a term inside addition is not.
This Secondary 3 G2 Mathematics tutor guide for Bukit Timah families explains algebraic fractions: simplification checks using worked examples and practical checking habits. Follow the child’s school chapter list to choose the relevant questions.
Factor before cancelling
(x²−9)/(x−3)=(x−3)(x+3)/(x−3)=x+3 for x≠3.
To confirm understanding, change the given values and solve independently. Explain why the same relationship applies, and check the original restrictions, units or data.
Keep restrictions
The simplified x+3 can be evaluated at x=3, but the original fraction cannot. The original restriction x≠3 must remain.
To confirm understanding, change the given values and solve independently. Explain why the same relationship applies, and check the original restrictions, units or data.
No cancellation across addition
(x+2)/x is not equal to 2 for general x. Splitting gives 1+2/x when x≠0.
To confirm understanding, change the given values and solve independently. Explain why the same relationship applies, and check the original restrictions, units or data.
Multiply fractions
(2x/3)(9/x)=6 for x≠0. Multiply numerators and denominators, then cancel common factors.
To confirm understanding, change the given values and solve independently. Explain why the same relationship applies, and check the original restrictions, units or data.
Add fractions
1/x+1/(x+1)=(2x+1)/(x(x+1)), provided x≠0 and x≠−1.
To confirm understanding, change the given values and solve independently. Explain why the same relationship applies, and check the original restrictions, units or data.
Subtract carefully
1/(x−2)−1/x=2/[x(x−2)] for x≠0,2.
To confirm understanding, change the given values and solve independently. Explain why the same relationship applies, and check the original restrictions, units or data.
Check
Substitute a permitted simple value into the original and simplified expressions to detect sign or factorisation errors.
To confirm understanding, change the given values and solve independently. Explain why the same relationship applies, and check the original restrictions, units or data.
Seven-day revision plan
Day 1: identify the definitions. Day 2: reproduce one worked example. Day 3: change the numbers. Day 4: solve an unlabelled problem. Day 5: identify the first mistaken step. Day 6: combine this skill with a related chapter. Day 7: complete an independent retest after a delay.
Frequently asked questions
What should I do first? Identify what is known and what the question asks. How can I check my answer? Substitute into the original expression or data and verify the units. Why might an answer look correct but fail? A denominator restriction, unit conversion or interpretation can be wrong even when arithmetic is neat.
Official syllabus and small-group tutorial context
Consult the 2027 SEC G2 Mathematics K210 syllabus for the precise assessment scope. The unchanged eduKateSG Mathematics tutorial reference describes three-pupil small-group teaching near Sixth Avenue. Confirm current Secondary 3 G2 tutor, fees, venue, class fit and timetable directly.
Related Secondary 3 G2 Mathematics guides
See Direct and Inverse Proportion, Algebraic Expansion and Box Plots and Quartiles.