Question

Descompuneti intrun produs de doi factori expresia 2x pătrat-x-1

Answer 1

2x^2-x-1 = 0

a = 2
b = -1
c = -1

∆ = b^2-4ac
∆ = 1+8
∆ = 9

x1 = (-b+√∆)/2a
x1 = (1+3)/4
x1 = 4/4
x1 = 1.

x2 = (-b-√∆)/2a
x2 = (1-3)/4
x2 = -2/4
x2 = -1/2.


a(x-x1)(x-x2) = 2(x-1)(x+1/2) = 2(x-1)[(2x+1)/2] = (x-1)(2x+1).



I hope I helped you :)