There's the simple but unobvious approach. Read this: Integral sec(x)
Then there's the more routine but tedious approach that involves the Weiestrass substitution. Read this: PlanetMath: Weierstrass substitution formulas
There's the simple but unobvious approach. Read this: Integral sec(x)
Then there's the more routine but tedious approach that involves the Weiestrass substitution. Read this: PlanetMath: Weierstrass substitution formulas