Question

(x-1)^2 +(x+1).(x-1)

Answer 1

Explanation:

what do we need to do ? just do the multiplications (and squaring is also a multiplication, just by itself) ?

we could do the exercise in full or just remember the results of

(a-b)² = (a-b)(a-b) = a² - 2ab + b²

and

(a+b)(a-b) = a² - b²

so, we get

x² - 2x + 1 + x² - 1

simplifying this is

2x² - 2x = 2(x² - x) = 2x(x - 1)