Proving This Trigonometric Identity

AI Thread Summary
The trigonometric identity to prove is (cscx + cotx) / (cscx - cotx) = (1 + 2cosx + cos^2x) / sin^2x. The left side is simplified to (1 + cosx) / (1 - cosx) using basic trigonometric identities. Multiplying the numerator and denominator by (1 + cosx) leads to the expression (1 + 2cosx + cos^2x) / (1 - cos^2x). Recognizing that 1 - cos^2x equals sin^2x allows for the final equality to be established. The identity is successfully proven through these algebraic manipulations.
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1. Prove:\frac{cscx +cotx}{cscx-cotx} = \frac{1+2cosx+cos^2x}{sin^2x}

Homework Equations


tanx = \frac{sinx}{cosx}
cotx = \frac{cosx}{sinx}
cscx
secx
cotx
sin^2x + cos^2x = 1

The Attempt at a Solution



Left side:
=\frac{cscx +cotx}{cscx-cotx}
=\frac{1/sinx + cosx / sinx}{1/sinx - cosx/sinx}
=\frac{1+cosx}{1-cosx}
 
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You are almost there! What could you multiply the numerator and denominator of your fraction to get the RHS?
 
You are almost there. What is sin^2x in terms of cos^2x?

EDIT: Just a minute late. -.-
 
=\frac{1+cosx}{1-cosx}
=\frac{1+cosx}{1-cosx} × \frac{1+cosx}{1+cosx}
= \frac{1+2cosx + cos^2x}{1-cos^2x}
=\frac{1+2cosx+cos^2x}{sin^2x}

thanks guys
 
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