Trig Identity Proof

[Tarmac27]

Hello,

Having some trouble proving this trig identity.




I took what I thought was the most intuitive step which was just combining fractions and simplifying using double angle identities for sine and cosine but what I ended up with was:

[math]\frac{cos(\theta)+sin(\theta)}{cos(\theta)-sin(\theta)}[/math]
Which Im not sure on how to transform into the required expression.

Thanks

 

[Otis]

[math]\frac{cos(\theta)+sin(\theta)}{cos(\theta)-sin(\theta)}[/math]
...not sure on how to transform [that] into the required expression.

Hi Tarmac. Instead, how about transforming the required expression into your result above -- the same way (by combining fractions).

That'll give you the reverse of the steps you seek.

?

 

[Pedja]

[math]\frac{cos(\theta)+sin(\theta)}{cos(\theta)-sin(\theta)}[/math]
Which Im not sure on how to transform into the required expression.

Just divide both the numerator and denominator by [imath]\cos(\theta)[/imath] .

 

[Tarmac27]

Awesome thanks for the help guys.