Find Integral of sin(x) / cos(x)^2 - Homework Help

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SUMMARY

The integral of sin(x) / cos(x)^2 can be simplified using the identity sin(x) / cos(x)^2 = tan(x)sec(x). A substitution method is recommended, specifically using u = cos(x), which leads to the integral of [(-2*u)/(1-u^2)]/-2. This approach clarifies the connection to the integral of sin(x)/cos^2(x) and facilitates easier computation.

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Homework Statement



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



Homework Equations



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


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

or

try to see 1/x connection
 
Last edited:
\int \frac{sinx}{cos^2x} dx

\equiv \int \frac{sinx}{cosx} \times \frac{1}{cosx}dx

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


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

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