Question

f(x) = x² -8 + 15 preciso saber a raiz quadrada dessa

Answer 1

Resposta:

(x) = -x² + 4x – 4

Δ = b² -4.a.c

Δ = 4² -4. -1. (-4)

Δ = 16 - 16

Δ = 0

X² = -b ± √Δ/2

X² = -4 ± 0/-2

X1 = -4/-2 = 2

X2 =-4/-2 = 2

Answer 2

Resposta:

x²- 8 + 15 = 0

a= 1   b= -8 c= 15

_calculo_

X = -b±√b²-4.a.c/2.a

X = -(-8)±√(-8)²-4.1.15/2.1

X = -(-8)±√64-60/2

X = -(-8)±√4/2

X = -(-8)±2/2 --------------> X = -(-8)+2/2→X = 8+2/2 → X = 10/2→ X= 5

                                        X = -(-8)-2/2→X = 8-2/2 → X = 6/2 → X = 3

⇒ As raízes dessa função são 5 e 3.