f (x ) = t * x2 + t 2 * x
f ´( x ) = 2 * t * x + t2
2 * t * x + t2 = 0
2tx = - t2
2x = -t
x = -t / 2
f ( -t / 2 ) = t * (-t/2)2 + t 2 * (-t/2)
f ( -t/2) = -t3 / 4
S ( x | y )
S ( -t/2 |- t3 / 4 )
x = -t/2 => t = - 2x
einsetzen
y = -t3/4 =>-(-2x)3 / 4
ort ( x ) = 8 / 4 * x3
ort ( x ) = 2 * x3