Primitive of Reciprocal of x squared plus a squared/Examples

Examples of Use of Primitive of $\dfrac 1 {x^2 + a^2}$

Primitive of $\dfrac 1 {16 + x^2}$

$\ds \int \dfrac 1 {16 + x^2} \rd x = \dfrac 1 4 \arctan \dfrac x 4 + C$