Find the coefficients of x 7 and x 8 in the expansion of .

Question

Philoid · Accepted Answer

To find : coefficients of x⁷ and x⁸

Formula :

Here, a=2,

We have,

To get a coefficient of x⁷, we must have,

x⁷ = x^r

• r = 7

Therefore, the coefficient of x⁷

And to get the coefficient of x⁸ we must have,

x⁸ = x^r

• r = 8

Therefore, the coefficient of x⁸

Conclusion :

• coefficient of x⁷

• coefficient of x⁸