Question

How do you evaluate `(2\sqrt { 5} + 2) ^ { 2}`?

Answer 1

`24+8sqrt5`

Explanation:

#we use teh relationship

`(a+b)^2=a^2+2ab+b^2`

`:.(2sqrt5+2)^2=(2sqrt5)^2+2(2sqrt5)2+2^2`

now `(2sqrt5)^2=2sqrt5 xx2sqrt5=2xx2xxsqrt5xxsqrt5=4xx5=20`

`=>20+8sqrt5+4`

`24+8sqrt5`