a)
[4, 2, 4] + r·([4, 4, 2] - [4, 2, 4]) + s·([2, 4, 4] - [4, 2, 4]) = [0, 0, 0] + t·([4, 4, 4] - [0, 0, 0]) --> r = s = 1/3 und t = 5/6
b)
V = 1/3 * G * h = 1/3 * 1/2 * 2 * 2 * 2 = 8/6 = 4/3
c)
[4, 4, 2] + r·([2, 4, 4] - [4, 4, 2]) = [x, y, 0] --> x = 6 ∧ y = 4 ∧ r = -1
[4, 4, 2] + r·([2, 4, 4] - [4, 4, 2]) = [0, y, z] --> y = 4 ∧ z = 6 ∧ r = 2
d)
k: X = [4, 4, 2] + r·([3, 3, 4] - [4, 4, 2]) = [4, 4, 2] + r·[-1, -1, 2]
e)
[4, 2, 4] + r·([4, 4, 2] - [4, 2, 4]) + s·([2, 4, 4] - [4, 2, 4]) = [4, 4, 0] + t·([0, 0, 4] - [4, 4, 0]) --> r = 3 ∧ s = -1 ∧ t = - 1/2