Question

Integral help (posting, be a sec)

Answer 1

\[\int\limits_{}^{} 4x \sec(x) \tan(x) dx\]
I substituted U=4x and DV=sec x tan x

Now I am at
\[\int\limits_{}^{}4x \sec(x) \tan(x) dx = 4x \sec (x) -\int\limits_{}^{}\sec (x) 4 dx\]

I know the integral of sec x is ln abs(sec x tan x) +C...
what about that 4?

Answer 2

ah : )

Answer 3

4 is a constant multiple just bring it down in front

Answer 4

or actually the -4

Answer 5

and you need a plus sign in between sec and tan

Answer 6

Whoops! Yep I missed the negative. Thanks for reminding me of those 2 things myininya!

Answer 7

So would it be \[4x \sec x -4\ln \left| \sec x + \tan x \right| +C\]

Answer 8

Yep.

Answer 9

Thanks! Let my try to put that in the program.

Answer 10

Yay! A+++