How do you verify Cosxtanx/secx = sinxcosx ? Or just any helpful tips on how to prove/verify trig identities would be amazing! Thanks so much!

2 Answers
Feb 23, 2018

If you are a beginner to trigonometry,then I will refer you wikipedia to know the formulas.... Trigo is nothing but application of various formulas to prove identities.

Reference:- trigo formulas

Now,

#(cosx cdot tanx)/secx#

#=(cosx cdot sinx/cosx)/(1/cosx)#

#=sinx/(1/cosx)#

#=sinx cdot cosx" "#[multiplying both nominator and denominator by #cosx#]

Hope it helps...
Thank you...

Feb 23, 2018

Try expanding the #tan# and #sec# into their #sin# and #cos# parts.

Explanation:

#(cos(x)tan(x))/sec(x) = (cos(x)*(sinx/cosx))/(1/cosx)#

You can now just do some simple cancelling and there's your answer

Try to expand any functions that aren't sine or cosine into sine or cosine and see if that helps. If that doesn't, you probably wanna try to multiply by some trigFunction/trigFunction to get the result you want, or maybe apply an identity.