Question

Determine as raízes da
equação: 7x elevado a 2 + 13x -2=0

s={-2,1/7)
s={-2, 7)
s={3,4)
Me ajudem pfvv​

Answer 1

Resposta:

s={-2, 1/7)

7x² + 13x -2=0

a=7

b=13

c=-2

∆=b²-4.a.c

∆=(13)²-4.7.-2

∆=169+56

∆=225

$x = \frac{ - 13- \sqrt{225} }{2 \times 7}$

$x = \frac{ - 13 -15 }{14}$

$x = \frac{ - 28}{14}$

$x = - 2$

$x = \frac{ - 13 + \sqrt{225} }{2 \times 7}$

$x = \frac{ - 13 + 15}{14}$

$x = \frac{2}{14}$

$x = \frac{1}{7}$