Question

1.Rozwiąż równanie

a)

b)

Answer 1

x²-x-2=0

Δ=1-4*1*(-2)=9     [Δ=b²-4ac]

√Δ=3

x1=(1-9)/2=-4      [x1=(-b-√Δ)/2a]

x2=5                    [x1=(-b+√Δ)/2a]

 

x²-10x+25=0        [(a-b)²=a²-2ab+b²]

(x-5)²=0

x-5=0

x=5