Solve sin(t) cos(2t)=b1 sin(t)+b2 sin(2t)+b3 sin(3t)

[aqsa]

sin(t) cos(2t) = ??

ok so i have to find the values for b1,b2 and b3...but i am clueless on how to find them
can anyone help?

sin(t) cos(2t) = b1 sin(t) + b2 sin(2t) + b3 sin(3t):

i thought of converting it to complex but that did not help much!

 

[dextercioby]

Use this

http://en.wikipedia.org/wiki/Trigonometric_identity#Product-to-sum_and_sum-to-product_identities

Wow, what do you know? We referenced the same page...

 

[bob1182006]

I would go with converting the product on the left to a sum, then expanding until you get the sinusoids on the right.
http://en.wikipedia.org/wiki/List_o...#Product-to-sum_and_sum-to-product_identities

 

[aqsa]

o yeah..forgot about those! thanks guys!