Question

"(x+1).(x-1)-2(x-1)=(x-1)²-3(x+1)"


"(x+1)²=2(x+1)"

Answer 1

a)

(x + 1). (x - 1) - 2.(x - 1) = (x - 1)² - 3.(x + 1)
x² - x + x - 1 - 2x + 2 = x² - 2x + 1 - 3x - 3
x² - 1 - 2x + 2 = x² - 5x - 2
2 - 1 - 2x = - 5x - 2
1 - 2x = - 5x - 2
1 + 2 =  - 5x + 2x
3 = - 3x
- 3x = 3 ( - 1)
3x = - 3
x = - 1

b)

(x + 1)² = 2(x + 1)
x² + 2x + 1 = 2x + 2
x² + 2x - 2x + 1 - 2 = 0
x² - 1 = 0
x = √1
x = 1 e x = - 1