1. Which of the following is an identity?
- Ax2 = 4
- Bx2 − 5x + 6 = 0
- C2x + 3 = 7
- D(x + 1)2 = x2 + 2x + 1
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Answer: D. An identity is true for every value of x. The others are conditional equations, true only for particular values.
By Team Megalecture · Updated 4 Nov 2026
10 exam-style questions on Partial fractions, each with the answer and a short explanation. Ten of them are below to try. The chapter test draws ten fresh questions each time and is marked the moment you finish, with your score by topic.
10 questions · 1 topics · 10 per test
Try each one, then open the answer. These ten stay the same; the test draws new ones every time.
Answer: D. An identity is true for every value of x. The others are conditional equations, true only for particular values.
Answer: A. 5x + 1 = A(x + 2) + B(x − 1). x = 1: 6 = 3A, A = 2. x = −2: −9 = −3B, B = 3. Check: 2(x + 2) + 3(x − 1) = 5x + 1.
Answer: D. The fraction is improper, so divide first: (x2 + 1)/(x2 − 1) = 1 + 2/(x2 − 1), and 2/(x2 − 1) = 1/(x − 1) − 1/(x + 1).
Answer: D. x2 + 4 cannot be factorised over the reals, so its numerator must be linear, Bx + C. Factorising it as (x + 2)(x − 2) is wrong: that is x2 − 4.
Answer: D. x = A(x − 1) + B. Put x = 1: B = 1. Compare x coefficients: A = 1. Check: (x − 1) + 1 = x.
Answer: B. A repeated linear factor (x + 2)2 needs a term for each power: B/(x + 2) and C/(x + 2)2. The factor x − 1 is not repeated.
Answer: A. 1 = Ax(x + 1) + B(x + 1) + Cx2. x = 0 gives B = 1; x = −1 gives C = 1; the x2 terms give A + C = 0, so A = −1.
Answer: B. 1 = A(x2 + 1) + (Bx + C)(x + 1). x = −1 gives A = 1/2; x2 terms: A + B = 0, B = −1/2; constants: A + C = 1, C = 1/2.
Answer: D. A fraction is improper when the degree of the numerator is at least the degree of the denominator. Here 3 ≥ 2; in the others the numerator has lower degree.
Answer: B. 1 = A(x + 1) + B(x − 1). x = 1 gives A = 1/2; x = −1 gives B = −1/2. Without the 1/2 the difference would be 2/(x2 − 1).
10, each with the answer and a short explanation, across 1 topics: Resolving into partial fractions. Every chapter test draws ten of them, so you can take it many times.
Yes. The test, the answers and the explanations are free and need no sign-up. Sign in only if you want your scores kept across devices.
The moment you press Finish: your score, the right answer and an explanation for every question, and the ones you got wrong saved in My mistakes to retry.
Yes. In practice mode and on your results you can switch the explanations to Urdu.
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