MHB Stuck on a trigonometric identity proof....

[Riwaj]

$\frac{1 -\cos A}{1 + \cos A} = (\cot A - \csc A)^2$

 

[castor28]

Re: please prove it i am stuck ...

$\frac{1 -\cos A}{1 + \cos A} = (\cot A - \csc A)^2$

Hi Riwaj,

What did yo try so far ?

 

[HallsofIvy]

Re: please prove it i am stuck ...

My approach would be to change the cosecant and cotangent on the right side to sine and cosine, then do the indicated operations on the right.

 

[Greg]

Here's the start of another approach:

$$\frac{1 - \cos x}{1 + \cos x} \cdot \frac{1 - \cos x}{1 - \cos x} = \frac{1 - 2\cos x + \cos^2 x}{\sin^2 x}$$

 

[Riwaj]

oh ... thank you everyone i got it now