First simplify, then evaluate: (x + 2) (x + 3) + 3 (x-1) (x + 1) - (2x-1) (2x + 3), where x = - 2 Come on!

First simplify, then evaluate: (x + 2) (x + 3) + 3 (x-1) (x + 1) - (2x-1) (2x + 3), where x = - 2 Come on!

:(x+2)(x+3)+3(x-1)(x+1)-(2x-1)(2x+3),
=x²+5x+6+3x²-3-4x²-4x+3
=x+6
When x = - 2
The original formula = - 2 + 6
=4

First simplify, then evaluate: 2 (x + 5) (x-4) - 3 (X-6) (x + 1), where x = 2

2 (x + 5) (x-4) - 3 (X-6) (x + 1), = 2 (x2 + x-20) - 3 (x2-5x-6), = 2x2 + 2x-40-3x2 + 15x + 18, = - x2 + 17x-22, when x = 2, the original formula = - 4 + 17 × 2-22 = 8

First simplify, then evaluate: 3-2 (x + 1) (X-2) + X (x-1) - 6, where x = 1 / 2

3-2(x+1)(x-2)+x(x-1)-6
=3-2(x^2-x-2)+x^2-x-6
=3-2x^2+2x+4+x^2-x-6
=-x^2+x+1
x=1/2
The original formula = - 1 / 4 + 1 / 2 + 1 = 5 / 4