SOLUTION: How do I prove that
1-2cos^2x = sinxcosx(tanx-cotx)
I'm really confused at trigonometric identities that involve reciprocal in general.
Algebra ->
Expressions-with-variables
-> SOLUTION: How do I prove that
1-2cos^2x = sinxcosx(tanx-cotx)
I'm really confused at trigonometric identities that involve reciprocal in general.
Log On
Question 919184: How do I prove that
1-2cos^2x = sinxcosx(tanx-cotx)
I'm really confused at trigonometric identities that involve reciprocal in general. Found 2 solutions by ewatrrr, Alan3354:Answer by ewatrrr(24785) (Show Source):
You can put this solution on YOUR website! sinxcosx(tanx-cotx)
( cosx/sinx)(sinxcosx)(tan^2x - 1)
cos^2 (tan^2x - 1)
sin^2 - cos^2
(1 - cosx^2) - cosx^2
1 - 2cosx^2
You can put this solution on YOUR website! How do I prove that
1-2cos^2x = sinxcosx(tanx-cotx)
===============
Convert tan and cot to sine & cosine
1-2cos^2x = sinxcosx(sin/cos - cos/sin)
1 - 2cos^2x = sin^2 - cos^2
----
Can you do the rest?
