Question

A=(x-1) e B=(x+1) calcule (A-B)²

Answer 1

a = (x - 1)
b = (x + 1)

= (A - B)² = A² - 2.A.B + B²
= A² - 2.A.B+ B²
= (x - 1)² - 2.(x - 1).(x + 1) + (x + 1)²
= x² - 2x + 1 - 2.(x² - 1) + x² + 2x + 1
= x² - 2x + 1 - 2x² + 2 + x² + 2x + 1
= 1 + 2 + 1
= 3 + 1
= 4