Solving Sinusoids: Expressing 8.5sin(290t+325) in Different Forms

[Moneer81]

Homework Statement

Express 8.5sin(290t+325) as C1cos(wt)+C2sin(wt)

Homework Equations

The previous parts of the problem actually ask to find the wave equation itself and write it in different forms. So the above wave equation can also be expressed as 8.5cos(290t-125) or as -8.5cos(290t+55) etc.

The Attempt at a Solution

Can I use the following trig identity: A cos (wt) + B sin (wt) = (A^2 + B^2)^1/2 cos (wt + tan^-1 (-B/A)) ?

 

[Dick]

It's easier than that. Use sin(a+b)=sin(a)*cos(b)+cos(a)*sin(b).