Question

E(x)=(3x-1)²-7(x+1)(x-2)-(x+3)²

vreau seriozitate !!!!!
dau coroana !!!!!!!!​

Answer 1

$= 9 {x}^{2} - 6x +1 + ( 7x + 7) \times (x - 2) - {x}^{2} + 6x + 9 =$

(a+b)²= a²+2ab+b²

(a-b)²=a²-2ab+b².

astea sunt formulele pe care le folosești

$9 {x}^{2} - 6x + 1 + 7 {x}^{2} - 14x + 7x - 14 - {x}^{2} + 6x + 9$

$15 {x}^{2} - 7x - 4 =$