∫ x / (x^4 - 6x^2 + 9) dx
= ∫ x / (x^2 - 3)^2 dx
z = x^2 - 3
1 dz = 2x dx
dx = 1/(2x) dz
= 1/2 * ∫ 1 / z^2 dz = -1 / (2z)
Resubstituieren
= -1 / (2(x^2 - 3)) + C
∫ 1/(3·x^2 + 9) dx = 1/9 * ∫ 1/(x^2/3 + 1) dx
Substitution z = x/√3
...
∫ sin(x) * cos(x) dx
Substitution z = sin(x)
...
Schaffst du den Rest dann alleine ?