integral of 1/((x+1)^2(x^2+1))

Lösung

\int \frac{1}{( x + 1 ) ^{2} ( x ^{2} + 1 )} d x

\frac{1}{2} ln ∣ x + 1 ∣ - \frac{1}{2 ( x + 1 )} - \frac{1}{4} ln x^{2} + 1 + C

Schritte zur Lösung

\int \frac{1}{( x + 1 ) ^{2} ( x ^{2} + 1 )} d x

Ermittle den Partialbruch von

\frac{1}{( x + 1 ) ^{2} ( x ^{2} + 1 )} : \frac{1}{2 ( x + 1 )} + \frac{1}{2 ( x + 1 ) ^{2}} - \frac{x}{2 ( x ^{2} + 1 )}

= \int \frac{1}{2 ( x + 1 )} + \frac{1}{2 ( x + 1 ) ^{2}} - \frac{x}{2 ( x ^{2} + 1 )} d x

Wende die Summenregel an:

\int f (x) \pm g (x) d x = \int f (x) d x \pm \int g (x) d x

= \int \frac{1}{2 ( x + 1 )} d x + \int \frac{1}{2 ( x + 1 ) ^{2}} d x - \int \frac{x}{2 ( x ^{2} + 1 )} d x

\int \frac{1}{2 ( x + 1 )} d x = \frac{1}{2} ln ∣ x + 1 ∣

\int \frac{1}{2 ( x + 1 ) ^{2}} d x = - \frac{1}{2 ( x + 1 )}

\int \frac{x}{2 ( x ^{2} + 1 )} d x = \frac{1}{4} ln x^{2} + 1

= \frac{1}{2} ln ∣ x + 1 ∣ - \frac{1}{2 ( x + 1 )} - \frac{1}{4} ln x^{2} + 1

Füge eine Konstante zur Lösung hinzu

= \frac{1}{2} ln ∣ x + 1 ∣ - \frac{1}{2 ( x + 1 )} - \frac{1}{4} ln x^{2} + 1 + C