Question

2x^2+x-1=0 Пж Помогите ​

Answer 1

2x²+x-1=0

a=2; b=1; c= -1

D=b²-4ac=1²-4*2*(-1)=1+8=9

x_{1}=(-b-√D)/(2a)=(-1-√9)/(2*2)=(-1-3)/4=-4/4= -1

x_{2}=(-b+√D)/(2a)=(-1+3)/4=2/4=1/2=0,5