Question

Looking for answers to check (Integral in comment)

Answer 1

\[\int\limits_{?}^{?}dx/x^2\sqrt{4-x^2}\]

Answer 2

anyone there? lol? i got

\[-\sqrt{4-x^2}/2x+c\]

Answer 3

Hold on

Answer 4

still working lol?

Answer 5

tricky one, I think

Answer 6

still working lol?

Answer 7

if it helps to tell you it is a trig substitution i just need to find my mistake if i was wrong

Answer 8

still working lol?

Answer 9

the next one is going to be a trig sub too that i'm posting

Answer 10

I tried that, didn't help

Answer 11

still working lol?

Answer 12

trig sub? let x = 2sin(theta)

Answer 13

still working lol?

Answer 14

solve for dx and find a substitution for the sqroot

Answer 15

yeah but 1/x^2 is sticking out

Answer 16

still working lol?

Answer 17

i ended up getting 2cos(theta)/4sin^2(theta)cos(theta)

Answer 18

still working lol?

Answer 19

yeah but you can simly replace x^2 with your substitution of x, right?

so in other words you get 4sin^2(theta)

Answer 20

Oh I see

Answer 21

i'm going to post another in a sec if you want to try that one also to check my answer. I use this as a check because my teacher didn't give us the answers

Answer 22

ok sure

Answer 23

the answer is \[-\frac{\sqrt{4-x^2}}{4 x}\]