# Evaluating sin n(a+b)

• February 1st 2008, 10:27 AM
Ten_No_Ryu
Evaluating sin n(a+b)
Knowing that sin (a+b) = sin(a)cos(b)+sin(b)cos(a), is there a generic form for evaluating sin (n(a+b))?

Thanks for the help!
• February 1st 2008, 10:29 AM
colby2152
Quote:

Originally Posted by Ten_No_Ryu
Knowing that sin (a+b) = sin(a)cos(b)+sin(b)cos(a), is there a generic form for evaluating sin (n(a+b))?

Thanks for the help!

Plug and chug my friend!

$sin(n(a+b))=sin(na)cos(nb)+sin(nb)cos(na)$
• February 1st 2008, 10:31 AM
Ten_No_Ryu
Thanks!

It's been far too long since I've had a math class, and here I am in Calculus I. Fortunately, the TA has agreed to spend a few hours with myself and other students drilling (into our heads) the concepts from algebra, pre-cal, and trig that we've forgotten. If only he'd find a room we can use...