Question

The tThe term 10x3y2 is a term in which binomial expansion?

(x + y)5

(x + y)6

(5x + 2y)6

(x + y)8

Answer 1

(x + y)^5.

Explanation:

The (r+1)th term of (x + y)^n = nCr x^n-r y^r

Compare this with 10x^3 y^2 we get

nCr = 10 , n-r = 3 and r = 2 giving n = 3+2 = 5

5C2 = 10.

So the answer is (x + y)^5.