please explain about the part of multiplying fractions with x^2 as a denominator

YEEEEEET
Nov 18, 2018

#1**+3 **

I think this is supposed to be a demonstration of the binomial theorem.

\((a+b)^n = \sum \limits_{k=0}^n~\dbinom{n}{k}a^k b^{n-k}\)

In this case

\(a = 2\\ b= \dfrac{3}{x^2}\)

\(\left(2 + \dfrac{3}{x^2}\right)^4 = \sum \limits_{k=0}^4~\dbinom{4}{k}2^k\left(\dfrac{3}{x^2}\right)^{4-k}\)

you can plug in k=4, 0 to get a-e

Rom
Nov 18, 2018

#2**+1 **

yes i know how to do that but i am not sure on the part of after simplifying everything which leaves me with an interger to multiply k/x^2. this is where i struggle. thank you for helping

YEEEEEET
Nov 18, 2018