Question

Me ajuda a responder ainda e pra hj (×+1)2=×+7

Answer 1

(x + 1)² = x + 7

(a + b)² = a² + 2.a.b + b²

(x + 1)² = x + 7

x² + 2.x.1 + 1² = x + 7

x² + 2x + 1 = x + 7

x² + 2x - x + 1 - 7 = 0

x² + x - 6 = 0

Δ = b² - 4.a.c

Δ = 1² - 4 . 1 . -6

Δ = 1 - 4. 1 . -6

Δ = 25

Há 2 raízes reais.

x = (-b +- √Δ)/2a

x' = (-1 + √25)/2.1

x'' = (-1 - √25)/2.1

x' = 4 / 2

x'' = -6 / 2

x' = 2

x'' = -3