x²+√2x-4=0
Δ=2+16=18>0
x=(-√2±3√2)/2
x1=√2,x2=-2√2
x²+√2x-4=0
(x+2√2)(x-√2)=0
x+2√2=0,x-√2=0
x1=-2√2,x2=√2