1/(x + 3) + 1/(x + 2) = 1/(x^2 + 5·x + 6) + 1/x
1/(x + 3) + 1/(x + 2) = 1/((x + 2)·(x + 3)) + 1/x
x·(x + 2)/(x·(x + 2)·(x + 3)) + x·(x + 3)/(x·(x + 2)·(x + 3)) = x/(x·(x + 2)·(x + 3)) + (x + 2)·(x + 3)/(x·(x + 2)·(x + 3))
x·(x + 2) + x·(x + 3) = x + (x + 2)·(x + 3)
x^2 + 2·x + x^2 + 3·x = x + x^2 + 5·x + 6
x^2 - x - 6 = 0
x = 3 ∨ x = -2
-2 ist nicht im Definitionsbereich daher ist 3 die einzige Lösung.