1) 4x^2-4x+1=25
4x^2-4x-24=0
delta=b^2-4ac
=16-4 ori 4 ori (-24)
=16-16 ori (-24)
=16+384
=400
x1=(-b+√delta)/2a=(4+20)/2 ori 4=24/8=3
x2=(-b-√delta)/2a=(4-20)/2 ori 4= -16/8= -2
2) (x+1)^2+3=0
x^2+2x+1+3=0
x^2+2x+4=0
delta=b^2-4ac
=4-4 ori 1 ori 4
=4-4 ori 4
=4-16
= -12 ==> nu exista solutii (pt ca delta e < 0)
3) a) x^2=9
x1=√9=3
x2= -√9= -3
b) 3x^2=48
x^2=48/3
x^2=16
x1=√16=4
x2= -√16= -4
c) x^2-16=0
x^2=16
x1=√16=4
x2= -√16= -4