Math notes
Half angle identities for cosine: cos 0/2
+or- square root 1+cos0/2
Half angle identities for tangent: tan0/2
+or- square root 1-cos0/1+cos0
Half angle identities for sine:sine 0/2
+or- square root 1-cos0/2
cos(-x)/sin(-x)
-cotx
sin^2x+cos^2x
1
Double angle identities Cosine: cos20
1-2*sin^2 0
Double angle identities Cosine: cos20
2*cos^2 0-1
Double angle ldentities Sine: sin20
2*sino*cos0
Double Angle identities Tanget: tan20
2*tan0/1-tan^20
cos(2A)=cos(A+A)
cosA*cosA-sinA*sinA
difference of angles for cosine:cos(A-B)
cosA*cosB+sinA*sinB
sum of angles for cosine: cos(A +B)
cosA*cosB-sinA*sinB
Double angle identities Cosine: cos20
cos^2 0-sin^20
1+cot^2x
csc^2x
sin 2A =Sin(A+A)
sin(2A)= 2*sinA*cosA
sun of angles for sine:sin(A+B)
sinA*cosB+cosA*sinB
difference of angles for sine: sin(a-b)
sinA*cosB-cosA*sinB
1-cos^2x
sin^2x
sun of angles for tangent:tan(a+b)
tanA+tanB/1-tanA*tanB
difference of angles for tangent: tan(A-B)
tanA-tanB/1+tanA*tanB
sec^2x-1
tan^2x