Loading....

WAEC SSCE - Further Mathematics - 2022 (Objective)

Question 1 Report

Find the coefficient of \(x^2\) in the binomial expansion of \(\left(x+\frac{2}{x^2}\right)^5\)

Answer Details

(x+2x2)5

n = 5,  r = 4,  p = x  and q = 2x2

5C4 4 x4 4  (2x2
)1 = 5C4 4  2x4x2

5C4 4  2x2 2  = 5![5−4]!4!
 * 2x2

5∗4!4!∗2x2 5 ∗ 4 ! 4 ! ∗ 2
 = 5 * 2x2 2  = 10x2

The coefficient is 10.