Question

Reduce: H = (x+1)(x+2) - (x+ 5)(x- 2) + (x- 4)(x+1) - (x- 1)(x- 2).

Answer 1

(x+1)(x+2) - (x+ 5)(x- 2) + (x- 4)(x+1) - (x- 1)(x- 2)

x^2+3x+2 -(x^2+3x-10) + (x^2-3x-4) - (x^2-3x+2)

x^2+3x+2 -x^2-3x+10 + x^2-3x-4 - x^2+3x-2

2 + 10 -4 -2

12 -6

6