Question

integral(sqrt(4+x^2), x)

Answer 1

Integrals with this form: \[
\int \sqrt{a^2+b^2x^2}dx
\]Require the trig substitution \(x = \frac{a}{b}\tan(\theta)\).
It's just an integration technique you have to memorize to be good at integrals.
Integrals are tricky, because not all functions have an anti derivative.

Answer 2

how to get the ln.????

Answer 3

integral((sec(x))^3, x) how to solve it.. i stuck until this stage only.???