Question

1) Calcule:
a) 2x² + × -1 =0

b) 2x² + 2× -24 = 0

c) x² + 5x +6 = 0

Answer 1

Resposta:

2x²+x-1=0

a=2 b=1 c=-1

∆=b²-4.a.c

∆=1+8

∆=9

x=-b±√∆/2.a

x=-1±3/4

x'=1+3/4 x'=1

x"=1-3/4 x"=-1/2