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Finding an integral

  • Thread starter ns5032
  • Start date
28
0
1. Homework Statement

I would just like some help on how to find the integral of:
sin(x) / cos(x)^2



2. Homework Equations

integration by parts?
uv-integral of v(du)


3. The Attempt at a Solution
I tried using integration of parts with u = cos(x)^2 and dv = sin(x) but I just got myself in a bigger mess.

I noticed that sin(x) / cos(x)^2 was equal to tan(x)sec(x). Not sure if that helps though...

Help please?!
 

Answers and Replies

392
0
I'd go for a substitution.
 
24
0
Try the substitution cos(x)^2.
 
351
2
what's integral of [(-2*u)/(1-u^2)]/-2

or

try to see 1/x connection
 
Last edited:
rock.freak667
Homework Helper
6,230
31
[tex]\int \frac{sinx}{cos^2x} dx[/tex]

[tex]\equiv \int \frac{sinx}{cosx} \times \frac{1}{cosx}dx[/tex]

What is another way to write [itex]\frac{sinx}{cosx}[/itex]?
and similarly [itex]\frac{1}{cosx}[/itex]?


Should be pretty standard after you see it.
 
28
0
Got it. Thank you everyone.
 

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