Question

Integrate sin(3x)tan(3x)

Answer 1

Use \[ \tan(3x)=\frac{\sin(3x)}{\cos(3x)} \]

Answer 2

The antiderivative is \[ -1/3\,\sin \left( 3\,x \right) +1/3\,\ln \left( \sec \left( 3\,x
\right) +\tan \left( 3\,x \right) \right) \]

Answer 3

Is that an identity?

Answer 4

Yes it is.

Answer 5

Hmm... apparently I haven't made it quite that far in Calc class =P

Answer 6

thats simplest trigonometry

Answer 7

Well, maybe not simplest...
And it includes a natural log... and I hate logarithms.

Answer 8

Oh I thought you meant the tan=sin/cos :D the latter was an antiderivative of sin(3x)tan(3x) !

Answer 9

Oh! Haha xD
Yeah, you kinda have to know trigonometric identities to do trig Calc.

Answer 10

Thanks