Trigonometric Identity Puzzle: Solving (1-cosx)/(1+cosx) = (cscx-cotx)^2

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SUMMARY

The equation (1-cosx)/(1+cosx) = (cscx-cotx)^2 can be solved by manipulating both sides using trigonometric identities. The right side expands to csc^2x - 2cotxcscx + cot^2x, which simplifies to (1-2cosx+cos^2x)/sin^2x. By substituting cscx = 1/sinx and cotx = cosx/sinx, the equation can be transformed into a form that allows for further simplification. Multiplying both the numerator and denominator of the left-hand side by (1-cosx) aids in achieving equivalence between both sides.

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Homework Statement


(1-cosx)/(1+cosx) = (cscx-cotx)^2


Homework Equations


cscx = 1/sinx, cotx = cosx/sinx, sin^2x + cos^2x = 1


The Attempt at a Solution



I have tried many different attempts, but I can't seem to make one side like the other. I took the (cscx-cotx)^2 and expanded it to csc^2x - 2cotxcscx+cot^2x = (1-2cosx+cos^2x)/sin^2x. Alternatively, (1-2cosx+cos^2x)/1-cos^2x

I've done every rearrangement I can think of, but I can't figure how to pull one side out of the other. Any help is much appreciated.
 
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Substitute cscx = 1/sinx, cotx = cosx/sinx in the right side and get only sin and cos equation on the right side.I see you already done that:
(1-2cosx+cos^2x)/1-cos^2x = ((1-cosx)/(sinx))^2 is enoughLeft side:
(1-cos.x)/(1+cosx)
.. looks like multiplying both num and den by 1-cosx would help
 
Try multiplying top and bottom of the LHS by (1-cos x).
 

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