Question

Need help with this intergral

Answer 1

\[ \int\limits_{2x}^{x^2}\sqrt{t^2+1?}dt\]

Answer 2

let t = tan(u)

Answer 3

I don't understand

Answer 4

then you need to tell me what you dont understand.

Answer 5

\[\int\limits_{0}^{2x?}\sqrt{t^2?} + \int\limits_{0?}^{x^2?} \sqrt{t^2+1?} \], this is what i've done thats why I dont understand why t= tan(u)

Answer 6

im not sure why you would do that.

Answer 7

is your question as posted part of something else?

Answer 8

if we let t=tanu

dt/du = sec^2 u

dt = sec^2 u du

subbing in we get:

{S} sqrt(tan^2 u + 1) sec^2 u du

{S} sec u sec^2 u du

{S} sec^3 u du that should be simpler to integrate