Question

How do you multiply `(x -1) (x +1)`?

Answer 1

`= x^2-1`

Explanation:

• As per the identity:
  `color(blue)((a-b)(a+b) = a^2-b^2`

Here:
`color(blue)(a) = x`
`color(blue)(b)=1`

Applying the property to the expression
`color(blue)((x-1)(x+1) = x^2-1^2`

`=x^2-1`