f(x) = - (x + 1)^2 + 4 = - x^2 - 2·x + 3
f'(x) = - 2·x - 2
f(x) = 0 --> x = -3 ∨ x = 1
Tangenten in den Achsenschnittpunkten
t1(x) = f'(-3)·(x - (-3)) + f(-3) = 4·x + 12
t2(x) = f'(1)·(x - (1)) + f(1) = 4 - 4·x
t3(x) = f'(0)·(x - (0)) + f(0) = 3 - 2·x