Need help with the following trig identity. - Math Help Forum

$Math Help Forum$

$Go Back$		Math Help Forum > Pre-University Math Help > Trigonometry
$Reload this Page$ Need help with the following trig identity.

Download MHF Flyer

Mark Forums Read

$Reply$

#1

$Old$ January 6th, 2009, 02:25 PM

januaryair $januaryair is offline$

Newbie

Join Date: Jan 2009

Posts: 3

Country:

Canada

Thanks: 1

Thanked 0 Times in 0 Posts

$januaryair is on a distinguished road$

$Default$ Need help with the following trig identity.

Prove this trig identity: cos(x-y) / cos(x)sin(y) = cot(y) + tan(x)

THANKS!

$Reply With Quote$

Advertisement

#2

$Old$ January 6th, 2009, 03:00 PM

$craig's Avatar$

craig $craig is offline$

Generous Contributor

Join Date: Apr 2008

Location: Manchester

Posts: 363

Country:

England

Thanks: 63

Thanked 121 Times in 108 Posts

$craig will become famous soon enough$ $craig will become famous soon enough$

$Default$

$\frac{\cos(x-y)}{\cos(x)\sin(y)}$

using $\cos(x-y) = \cos(x)\cos(y)+\sin(x)\sin(y)$ ,

$\frac{\cos(x)\cos(y)+\sin(x)\sin(y))}{\cos(x)\sin(y)} \Rightarrow \frac{\cos(x)\cos(y)}{\cos(x)\sin(y)} + \frac{\sin(x)\sin(y))}{\cos(x)\sin(y)}$

I'm sure you can work out the rest

__________________
Craig

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

$Reply With Quote$

The following users thank craig for this useful post:
januaryair
$Donate to MHF$

$Reply$

trig identities prove

« cos (x - y) | Top | Need help verifying this(trig related): »

Thread Tools
$Show Printable Version$ Show Printable Version $Email this Page$ Email this Page
Display Modes
$Linear Mode$ Linear Mode $Hybrid Mode$ Switch to Hybrid Mode $Threaded Mode$ Switch to Threaded Mode

Posting Rules
You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is Off Trackbacks are Off Pingbacks are Off Refbacks are Off

Forum Jump

All times are GMT -7. The time now is 12:52 AM.

your link here Sponsors

rv solar, e-learning,

Math Help Forum is a community of maths forums with an emphasis on maths help in all levels of mathematics.
Register to post your math questions or just hang out and try some of our math games or visit the arcade.