Question

Using the binomial theorem, Find the first three terms in the expansion of (x^2+2y^3)^20

Answer 1

They are, of course,

20C0 (x^2)^20(2y^3)^0 + 20C1(x^2)^19(2y^3)^1 + 20C2 (x^2)^18(2y^3)^2
x^40 + 40x^38y^3 + 760x^36y^6