1. Powers of Sine and Cosine
   1. sine is odd and positive
      1. separate to one sine factor and an even set of factors
      2. convert even set to cosine using pyth. id.
      3. use substitution
   2. cosine is odd and positive
      1. separate to one cosine factor and an even set of factors
      2. convert set to sine using pyth. id.
      3. us substitution
   3. both are even and pos.
      1. use half angle identities to convert to odd power of cos
      2. use odd cosine rule
2. Powers of sec & tan
   1. secant is even and pos.
      1. separate to one sec^2 factor and an even set of factors
      2. convert set to tan using pyth id.
      3. use substition
   2. tan is odd and pos
      1. separate to one sectan
      2. convert rest to sec
      3. use substitution
   3. no sec and tan is even and pos
      1. convert one tan^2 to sec^2
      2. repeat
   4. otherwise
      1. convert to sin and cos
3. sin cos product w/ different angles
   1. use product to sum id
      1. sin(mx)sin(nx)=(1/2)(cos[(m-n)x]-cos[(m+n)x])
      2. sin(mx)cos(nx)=(1/2)(sin[(m-n)x]+sin[(m+n)x]
      3. cos(mx)cos(nx)=(1/2)(cos[(m-n)x]+cos[(m+n)x])
4. Other Useful Identities
   1. Pythagorean
      1. sin^2(x)+cos^2(x)=1
      2. 1+tan^2(x)=sec^2(x)
   2. Half Angle
      1. sin^2(x)=(1-cos(2x))/2
      2. cos^2(x)= (1+cos(2x))/2