Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Promoted
Prove the identity: csc(x) - sin(x) = cot(x) cos(x)?
Pls, help.
1 Answer
Relevance
- germanoLv 74 years ago
Hello,
cscx - sinx = cotx cosx
let's recall that:
cscx = 1 /sinx
cotx = cosx /sinx:
(1 /sinx) - sinx = (cosx /sinx) cosx
(1 - sin²x) /sinx = cos²x /sinx
let's apply the fundamental identity 1 = sin²x + cos²x:
[(sin²x + cos²x) - sin²x] /sinx = cos²x /sinx
(sin²x + cos²x - sin²x) /sinx = cos²x /sinx
cos²x /sinx = cos²x /sinx (Q.E.D.)
I hope it helps
Still have questions? Get your answers by asking now.