Question

Find the integral of dx/(sqrt(1+x)) from 0 to 8.

Answer 1

let u = 1+x
du = dx

∫du / sqrt(u) = ∫ u^(-1/2) du
= 2u^(1/2) = 2sqrt(x+1)

I'll let you do the computation

Answer 2

How did you get 2u^(1/2)?

Answer 3

Actually, let's just make u = x + 1, so du = dx, which means:

du/sqrt(u), which is the same as:

u^(-1/2) * du, now integrating:

2sqrt(u)

Replacing u:

2sqrt(x + 1).

Now if they want it from 0 to 8, we just solve as follows:

2sqrt(8 + 1) - 2sqrt(0 + 1)

= 6 - 2 = ?

Answer 4

If you need more help go here: http://www.youtube.com/watch?v=ZJ6sjCub4jg
That video helps with that specific type of question :-)

Answer 5

Thank you guys so much.

Answer 6

Thank you for letting me help you!

Signed:
\[Mangorox\]