Question Detail

MTH 101 Binomial Expansion Objective Question
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Question

If coefficients of x^2 and x^3 are equal in (ax - b)^5, find relation between a and b.
Options
A 3a^2b^3 = 10a^3b^2 → 3b = 10a
Correct Answer
B 10a^2b^3 = 10a^3b^2 → a = b
C 5a^2b^3 = 10a^3b^2 → b = 2a
D a^2b^3 = a^3b^2 → a = b
Correct Answer

Option A is the correct answer.

Detailed Explanation

T_3 = C(5,2) a^2 x^2 (-b)^3, T_4 = C(5,3) a^3 x^3 (-b)^2. Set |T_3|=|T_4| → 3a^2b^3 = 10a^3b^2 → 3b = 10a.

Hint

Compare absolute values of coefficients.

Question Info

Course: MTH 101
Topic: Binomial Expansion
Type: Objective
Difficulty: Not specified
Question 72 of 696
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