Integral with a Radical in the Denominator
Calculus
Evaluate the integral: $$ \int \frac{1}{x^2\sqrt{x^2-9}}\,\mathrm{d}x$$
A$\frac{\sqrt{x^2-9}}{9x}+C$
B$\frac{\sqrt{x^2-9}}{3x}+C$
C$\frac{x}{9\sqrt{x^2-9}}+C$
D$\frac19\ln\left
Ex+\sqrt{x^2-9}\right
F+C$