Question

Simplifique as expressoes:

a)(2x-3y) (2x+3y) - (3x-2y)²
b)3(m-1)² + 2 (1+m) (1-m)

Answer 1

a
4x² - 9y² - ( 9x² - 12xy + 4y²) =
4x² - 9y² - 9x² + 12xy - 4y² = -5x² -13y² + 12xy

b
3 ( m² - 2m + 1) + 2 ( 1 - m²) =
3m² - 6m + 2 + 2 - 2m² =
m² - 6m + 4 =
( m - 2)²