Question

Using the identities, simplify :

$(x-2)(x+2)$

Answer 1

Identify the identity being used, the question is in the form of $(a-b)(a+b)$ which is equal to $a^2-b^2$where $a=xandb=2$

$$\begin{gathered} (x-2)(x+2)=x^2-2^2 \\ =x^2-4 \end{gathered}$$

Hence the result is $x^2-4$