Question

Photo of question inside

Answer 1

What an I not seeing....

Answer 2

The error is from the first line. Let u=cos(x) not 1/cos(x)..

Answer 3

Bwhy though?

Answer 4

That's the proper substitution.

Answer 5

What rule says I cant choose sec ?

Answer 6

hmm antiderivative of that is ln cosx + c

Answer 7

Oh they used by parts. I have never used integration by parts to solve that integral only u substitution.

Answer 8

oops forgot -ln cos x + C

Answer 9

@jim_thompson5910

Answer 10

integration by parts is really unnecessary for this problem

Answer 11

@UsukiDoll I AGREE!

Answer 12

Yes I can do it another way but I want to know where the.mistake is

Answer 13

here's the problem the integral of tanx has it's own antiderivative identity...

Answer 14

so doing this by parts or even converting tanx into sinx /cosx is really whyy just why

Answer 15

what's that supposed to mean?

Answer 16

Im.playing

Answer 17

there's an anti derivative integral version of tanx .. works fine by itself... why this person even convert .. SO DUMB!

Answer 18

if someone really gives me that as an answer.. I will fail them!

Answer 19

Everyone keeps saying it's not the way to do or it.....but why is this wrong.

Answer 20

The problem asks to find the problem

Answer 21

When I learned integration by parts my prof said let U=LIATE (Logarithm, Inverse trig function, Algebraic, Trig function, Exponential function). So @zzr0ck3r take u to be tanx
du = sec^2x, dv=dx, v=x Try that!

Answer 22

Again, the question asks to find the problem with this proof.......

Answer 23

What proof? I thought it said identify the error. :P

Answer 24

yeahhh

Answer 25

The question shows what I showed, and it says find the error and fix it

Answer 26

oh I'll fix it alright ...