SOLUTION: Prove that: TanA - CotA = -2Cot2A

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Question 923335: Prove that:
TanA - CotA = -2Cot2A
Found 2 solutions by ewatrrr, lwsshak3:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
-2Cot2A = -2(1-Tan^2A)/2TanA) = (Tan^2A-1)/TanA = TanA - 1/TanA = TanA - CotA

Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Prove that:
TanA - CotA = -2Cot2A
***
use x for A
tanx-cotx=-2cot%5E2%28x%29
start with left side:

verified: left side=right side