ax² + bx + c
= a*( x^2 + (b/a)*x ) + c
= a*( x^2 + (b/a)*x + b^2/(4a^2) ) - b^2/(4a^2) ) ) + c
= a*( x + b/(2a)) ^2 - b^2/(4a^2) ) + c
= a*( x + b/(2a)) ^2 - b^2/(4a) + c
==> α=a ß=b/(2a) γ = c - b^2/(4a)
b) dann mit a*( x + b/(2a)) ^2 - b^2/(4a) + c = 0
a*( x + b/(2a)) ^2 = b^2/(4a) - c falls a≠0 also
( x + b/(2a)) ^2 = b^2/(4a^2) - c/a falls b^2/(4a^2) - c/a ≥0
x + b/(2a) = ±√ ( b^2/(4a^2) - c/a)
x = -b/(2a) ±√ ( b^2/(4a^2) - c/a)