a)
0 = x^2 - 16
x^2 = 16
x1 = -4
x2 = 4
b)
0 = (x + 2)^2 - 9
x^2 + 4x + 4 = 9
x^2 + 4x - 5 = 0
p-q-Formel:
x1 = -2 - √(4 + 5) = -2 - 3 = -5
x2 = -2 + √(4 + 5) = -2 + 3 = 1
c)
0 = x^2 + 3x
0 = x * (x + 3)
x1 = 0
x2 = -3
d)
0 = x^2 + 6x - 5
p-q-Formel:
x1 = -3 - √(9+5) = -3 - √14 ≈ -6,74
x2 = -3 +√(9+5) = -3 + √14 ≈ 0,74
e)
0 = x^2 - 12x + 36
p-q-Formel:
x1 = 6 - √(36 - 36) = 6
x2 = 6 + √(36 - 36) = 6
Also doppelte Nullstelle an x = 6