SOLUTION: Simplify the expression by using a double angle formula. 2sin((2pi)/(11))cos((2pi)/(11)) I think it may be sin((4pi)/(11)). I am not sure on this and I could use the help.

Algebra ->  Trigonometry-basics -> SOLUTION: Simplify the expression by using a double angle formula. 2sin((2pi)/(11))cos((2pi)/(11)) I think it may be sin((4pi)/(11)). I am not sure on this and I could use the help.      Log On


   

Question 596137: Simplify the expression by using a double angle formula.
2sin((2pi)/(11))cos((2pi)/(11))
I think it may be sin((4pi)/(11)).
I am not sure on this and I could use the help.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Using the identity

2*sin(x)*cos(x) = sin(2x)

we get



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So


which means you are 100% correct. Nice job.