Löse die folgenden biquadratischen Gleichungen ax4 + bx2 + c = 0

-3.5x4 + 31.5x2 - 49 = 0
 x1 = 1.41  x2 = -1.41
x3 = 2.65  x4 = -2.65		-2.5x4 - 2.5x2 = 0
 x1 = 0  x2 = 0
x3 = ◊  x4 = ◊
2.5x4 - 90 = 0
 x1 = ◊  x2 = ◊
x3 = 2.45  x4 = -2.45		-x4 + 3x2 = 0
 x1 = 1.73  x2 = -1.73
x3 = 0  x4 = 0
-5.5x4 - 71.5x2 - 220 = 0
 x1 = ◊  x2 = ◊
x3 = ◊  x4 = ◊		-2.5x4 + 2.5x2 + 75 = 0
 x1 = ◊  x2 = ◊
x3 = 2.45  x4 = -2.45
1.5x4 - 21x2 + 60 = 0
 x1 = 3.16  x2 = -3.16
x3 = 2  x4 = -2		3.5x4 - 28x2 + 24.5 = 0
 x1 = 1  x2 = -1
x3 = 2.65  x4 = -2.65
4x4 - 32x2 + 60 = 0
 x1 = 2.24  x2 = -2.24
x3 = 1.73  x4 = -1.73		-7.5x4 - 67.5x2 - 150 = 0
 x1 = ◊  x2 = ◊
x3 = ◊  x4 = ◊
-3.5x4 + 42x2 - 126 = 0
 x1 = 2.45  x2 = -2.45
x3 = 2.45  x4 = -2.45		2x4 = 0
 x1 = 0  x2 = 0
x3 = 0  x4 = 0
-0.5x4 - 3x2 - 4.5 = 0
 x1 = ◊  x2 = ◊
x3 = ◊  x4 = ◊		-1.5x4 - 9x2 = 0
 x1 = 0  x2 = 0
x3 = ◊  x4 = ◊
4x4 - 24x2 + 32 = 0
 x1 = 1.41  x2 = -1.41
x3 = 2  x4 = -2		6.5x4 + 58.5x2 + 52 = 0
 x1 = ◊  x2 = ◊
x3 = ◊  x4 = ◊
9.5x4 - 28.5x2 - 38 = 0
 x1 = ◊  x2 = ◊
x3 = 2  x4 = -2		-6x4 - 30x2 + 36 = 0
 x1 = 1  x2 = -1
x3 = ◊  x4 = ◊
3x4 + 9x2 - 54 = 0
 x1 = 1.73  x2 = -1.73
x3 = ◊  x4 = ◊		6x4 + 30x2 - 300 = 0
 x1 = 2.24  x2 = -2.24
x3 = ◊  x4 = ◊