re write in terms of sine and cosine: Tanx · Cotx

Question

e.mccormick · Answer

OK... so what is tanx in sine and cosine?  cotx?  In fact, if you know the relationship between tan and cot, you might see a shortcut.... unless you are not supposed to multiply it.

anonymous · Answer

tan= sinx/cosx
cot= cosx/sinx

anonymous · Answer

idk what to do after that

e.mccormick · Answer

Well, they are bing multiplied.  Right?  The $\cdot$ means that, right?

anonymous · Answer

yeah

e.mccormick · Answer

And if you multiply a fraction by its inverse you get?

anonymous · Answer

1?

e.mccormick · Answer

Yes.

anonymous · Answer

WOoo

anonymous · Answer

thanks you  got a few more questions though

e.mccormick · Answer

So any trig funtion times its inverse will be 1.  Which comes in handy...  Because multplying by one is a way to not change a value.

anonymous · Answer

this question ask to establish the identity
Cot theta times Sec theta = csc theta

e.mccormick · Answer

$\cot\theta\cdot\sec\theta = \csc\theta$
OK.  Know the rules of doing an identity?  Well, the one big rule for trig ones....

anonymous · Answer

no haha

e.mccormick · Answer

You can only work on one side of the = sign.  So you can't do things that would change both sides.

e.mccormick · Answer

Now, you get to pick which side you want to work.  Sometimes working the right is easier.  In this case, I bet working the left is.

anonymous · Answer

what am i supposed to do?

e.mccormick · Answer

And, there is a cheat you can use....  work both sides to the same thing on scratch paper... then write out one side the same way, then the other side backwards right below it, as if you did it all as one thing.


In this case, put everything on the left in terms of sine and cosine.  See what happens.  That is always an OK way to start.

anonymous · Answer

ok so |dw:1374129586624:dw|