Trigonometry identity sin(pi)cos(wpi)+cos(pi)sin(wpi)

[izen]

Homework Statement

Hi guys, How can sin(∏)cos(ω∏)-cos(∏)sin(ω∏) = sin(ω∏)? please guide me trigonometry identity to apply with this?

Homework Equations

The Attempt at a Solution

 

[Dick]

sin(pi)=0, cos(pi)=(-1). So, of course, sin(∏)cos(ω∏)-cos(∏)sin(ω∏) = sin(ω∏). I'm not sure what that has to do with what follows.

 

[izen]

sin(pi)=0, cos(pi)=(-1). So, of course, sin(∏)cos(ω∏)-cos(∏)sin(ω∏) = sin(ω∏). I'm not sure what that has to do with what follows.

Ohhh :shy: Just been thinking about using trig identity, thank you Dick !