Question

Evaluate integral

Answer 1

\[\int\limits_{}^{}(sint*dt) / (1-\sin^2(t))\]

Answer 2

HI!!

Answer 3

Hi :)

Answer 4

does it help to know that the denominator is \(\cos^2(x)\)?

Answer 5

Yeah I figured that out! I'm setting u=sinx though

Answer 6

bad idea

Answer 7

try \(u=\cos(x)\)

Answer 8

ok! how do you know when it is a bad idea to substitute something in for u?

Answer 9

okay, I got sect :)

Answer 10

once you have
\[\int \frac{\sin(x)}{\cos^2(x)}dx\] if you make \(u=\sin(x)\) then how are you going to get rid of the square on the cosine?

Answer 11

substitute cos^2 into sin^2-1?

Answer 12

it is not really a substitution, it is an identity

Answer 13

oh okay! I think I got the answer after u=cost thanks :)

Answer 14

\[\color\magenta\heartsuit\]