Question

z elevado a 2 - 2z - 1 = 0

Answer 1

A)1( SERIA 1z²)

B)2

C)-1

∆=b²-4.a.c

∆=2²-4.1.(-1)

∆=4-4.(-1)

∆=4+4

∆=8

Bhaskara:

$\frac{z = - b + - \sqrt{d} }{2.a} \: seria \: x = ..\\ \\ \frac{z = - 2 + \sqrt{8} }{2.1} \\ \\ \frac{z = -2 + 2 \: 82}{2.1} \\ \\ \frac{ -0 \: 82}{2} \\ \\ z = - 0.41 \\ \\ \frac{z = - 2 - 2.82}{2} \\ \\ \frac{z = - 4.82}{2 } \\ \\ z = - 2.41 \\ \\ (2.41 \: 0.41)$