Question

[x^2+2y]^3
expand it

Answer 1

x^6 + 6x^4 y + 12x^2 y^2 + 8y^3.

Explanation:

Using the Binomial Theorem:

(x^2 + 2y)^3 = (x^2)^3 + 3C1 (x^2)^2 (2y) + 3C2 x^2 (2y)^2 + (2y)^3

= x^6 + 3*x^4*2y + 3*x^2*4y^2 + 8y^3

= x^6 + 6x^4 y + 12x^2 y^2 + 8y^3.

Answer 2

`(a + b) {}^(3) = a {}^(3) + 3a {}^(2) b + 3ab {}^(2) + b {}^(3) \\ \\ x {}^(6) + 6x {}^(4) y + 12x {}^(2) y {}^(2) + 8y {}^(3)`