Laplace transform of phase-shifted sinusoid

[KingNothing]

Homework Statement

Find the laplace transform of $$f(t)=sin(4t+\frac{\pi}{3})u(t)$$.
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Homework Equations

Definition of laplace transform, and properties: http://en.wikipedia.org/wiki/Laplace_transform#Properties_and_theorems"

The Attempt at a Solution

I have a feeling that I need to use the time-shift property of the transform, but I need just a bit more direction on the strategy.

 

[Raskolnikov]

Use trig summation identity to simplify:

$$f(t) = \left[ sin(4t)cos(\frac{\pi}{3}) + cos(4t)sin(\frac{\pi}{3}) \right] u(t).$$

Can you finish from here?

 

[gomunkul51]

When your step function starts, at t=0 ?