Question

Simplify the following expressions:

`(sqrt8 - sqrt2)(sqrt8 + sqrt2)`

Answer 1

We know that `(a - b)(a + b) = a^2 - b^2`. We will use this porperty to simplify the expression

`(sqrt8 - sqrt2)(sqrt8 + sqrt2)`

`∴(sqrt8 - sqrt2)(sqrt8 + sqrt2) = (sqrt8)^2 - (sqrt2)^2`

`= sqrt8 xx sqrt8 - sqrt2 xx sqrt2`

`= (8^2)^(1/2) - (2^2)^(1/2)`

`=8^1 - 2^1`

= 6

Hence the value of expression is 6