Question

Find the 5^th term of expansion of `(x^2 + 1/x)^10`?

Options

• 260 x⁸

• 5040 x⁸

• 210 x⁸

• 420 x⁸

Answer 1

210 x⁸ 

Explanation:

In the expansion of `(x^2 + 1/x)^10`,

5^th term = T₅ = T₄₊₁ = `""^10C_4 (x^2)^(10 - 4) (1/x)^4`

∴ T₅ = `(10 xx 9 xx 8 xx 7)/(4 xx 3 xx 2 xx 1) x^12 xx 1/x^4`

T₅ = 210 x⁸