2) 4x^{2}-8x+1=0
a=4,b=-8,c=1
Δ=b^{2}-4a c
Δ=(-8)^{2}-4·4·1
Δ=64-16
Δ=48 > 0 => x1,x2 = \frac{8 +- \sqrt{48} }{8}
x1,x2 = \frac{8 +- 4\sqrt{3} }{8}
x1 = \frac{8+4\sqrt{3}}{8} (dai factor comun pe 2)
x1 = \frac{2(4+2\sqrt{3})}{8} (simplifici 4 cu 8)
x1 = \frac{4+2\sqrt{3}}{4} (simplifici fractia cu 2)
x1 = \frac{2+\sqrt{3}}{2}
