Find the binomial expansion of (125+75x)13\displaystyle (125 + 75x)^{\frac{1}{3}}(125+75x)31 in ascending powers of xxx, up to and including the term in x3x^3x3.
[4]
b.
Find the range of values of x x\,x for which this expansion is valid.
[1]
1.4.1 Binomial expansion for positive integer n Questions
