SOLUTION: Prove that the following equation is an identity 4sin(x/4)cos(x/4)cos(x/2)=sinx

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Question 243254: Prove that the following equation is an identity
4sin(x/4)cos(x/4)cos(x/2)=sinx
Answer by Edwin McCravy(20056)   (Show Source): You can put this solution on YOUR website!


Write the  in the left side as 



Put parentheses around 



Use the identity 
using , 
or 
to replace what we just put in parentheses:


 


Now use that same identity again, ,
this time using , 
or  to replace the left side:



Edwin
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