How does this simplify to sin3x:

sinxcos2x + sin2xcosx = sin3x

this is part of parametric equations ch10 in my Calculus textbook. I am not sure if they used a trig identity or pure algebra.

thank you

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- Jan 9th 2010, 02:28 PMbhaskar2simplifying trignometry in calculus
How does this simplify to sin3x:

sinxcos2x + sin2xcosx = sin3x

this is part of parametric equations ch10 in my Calculus textbook. I am not sure if they used a trig identity or pure algebra.

thank you - Jan 9th 2010, 03:16 PMArchie Meade
Are you asking a question different to sinAcosB+cosAsinB=sin(A+B) ?

- Jan 10th 2010, 08:35 PMbhaskar2
Thanks for the help. You are right about that identity.

I knew the Calculus but it is only the trig and algebra which costs me points on the Calculus exam.

Thanks again. So How do I give you exp points for helping me out so the green balls will increase on your account.

- Jan 11th 2010, 04:05 AMArchie Meade
Here's a reasonable list of trig identities.

I don't know about the green dots either!

you're welcome. - Jan 11th 2010, 04:39 AMHallsofIvy