Question

int_{0}^{3} x/(sqrt{x^2+16}

Answer 1

let\[x =\tan \theta\]

Answer 2

:) thx

Answer 3

On closer inspection, you don't need trig sub, u sub would suffice. I never noticed until after I worked it out myself. But hey, good practice for trig sub. When you get it on the test you going to knock it out of the park.

Answer 4

shouldnt x = 4tan(t)? that way; when you square it you get:

sqrt(16 tan^2(t) + 16) = sqrt(16(tan^2+1))) = 4sec^2

Answer 5

err.... 4 sec :)

Answer 6

Yes. I think he picked that up.