Expand an expression using the binomial theorem (Part 1)

Binomial theorem: ((a+b)^n=a^n+na^(n−1) b+(n(n−1))/2! a^(n−2) b^2+(n(n−1)(n−2))/3! a^(n−3) b^3+…+b^n )

Q1. Use the binomial theorem to expand (a+b)^5.

Q2. Use the binomial theorem to expand (1/x+1/y^2 )^3.