prove the identity: cscx-sinx=cosxcotx

remember that in a proof you can only change one side

Question

prove the identity: cscx-sinx=cosxcotx

remember that in a proof you can only change one side

anonymous · Answer

(1/Sin) - Sin = Cos*Cos/Sin
(1-Sin^2)/Sin = Cos^2/Sin
Use the fact that 1=Sin^2+Cos^2
(Sin^2+Cos^2-Sin^2)/Sin = Cos^2/Sin
Cos^2/Sin=Cos^2/Sin, qed :)

anonymous · Answer

oh wait.. well i didn't technically change cosxcotx, but i did lol

anonymous · Answer

yah you cant change it!

anonymous · Answer

its easy to do if you can change it

anonymous · Answer

Sighh stupid arithmetic, it's easy to do if u don't change it as well..

Csc-Sin=Cos*Cot

(1/Sin)-Sin=(1-Sin^2)/Sin=Cos^2/Sin=(Cos/Sin)*Cos=Cot*cos

anonymous · Answer

woah can you please do it the other way its all thrown together 
Thanks :)

anonymous · Answer

OMG man, copy+paste works magic, the equality sign separates them all, you're good to go.

anonymous · Answer

(1/Sin)-Sin=
(1-Sin^2)/Sin=
Cos^2/Sin=
(Cos/Sin)*Cos=
Cot*cos

anonymous · Answer

Im struggling to understand how the -sinx disappears

anonymous · Answer

It's magic my friend!

anonymous · Answer

how??

anonymous · Answer

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