Question

(a - b)^2 - c^2, quando a = 2/3, B = 1 e C = -1

Answer 1

$( \frac{2}{3} - 1) {}^{2} - ( - 1) {}^{2} = \\ \\ ( - \frac{1}{3} {)}^{2} - 1 = \frac{1}{9} - 1 = - \frac{8}{9}$