+0  
 
0
60
2
avatar

Can anyone provide steps that show that

 

cos2x / (cosx - sinx) = cosx + sinx

 

?? Thanks!

Guest Sep 19, 2018
 #1
avatar+90053 
+1

cos2x / (cosx - sinx) = cosx + sinx 

 

Note that cos 2x  =  cos^2x  - sin^2 x....= (cos x - sin x) (cos x + sinx ).....so we have

 

(cos^2x - sin^2x )  / ( cosx - sin x)

 

(cosx + sin x) (cos x - sin x)  / (cos x - sin x )        divide out the  (cosx - sinx)

 

cos x + sin x  =    the right hand side

 

 

cool cool cool

CPhill  Sep 19, 2018
 #2
avatar
+1

Thank you so much! Didnt think of the (a+b)*(a-b) rule!

Guest Sep 19, 2018

10 Online Users

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.