Math

Trigonometry

• sin(a+b)=sin(a)cos(b)+sin(b)cos(a)
• sin(a-c)=sin(a)cos(c)-sin(c)cos(a)
• cos(a+b)=cos(a)cos(b)-sin(a)sin(b)
• cos(a-b)=cos(a)cos(b)+sin(a)sin(b)
• cos(2a)=$$cos^2(a)-sin^2(a)$$
• $$2*cos^2(a)-1=cos(2a)$$
• $$cos^2(a)=(1/2) * (1+cos(2a))$$