How can we help?

You can also find more resources in our Help Center.

12 terms

Trig Identities

Uncommon sum-diff/double angle, power-reducing/half angle, StP, PtS
STUDY
PLAY
(tan(a)+tan(b))/(1-tan(a)tan(b))
tan(a+b)
(tan(a)-tan(b))/(1+tan(a)tan(b))
tan(a-b)
2tan(a)/(1-tan²(a))
tan(2a)
(1-cos(2a))/2
sin²(a)
(1+cos(2a))/2
cos²(a)
2sin((a+b)/2)cos((a-b)/2)
sin(a)+sin(b)
2cos((a+b)/2)sin((a-b)/2)
sin(a)-sin(b)
2cos((a+b)/2)cos((a-b)/2)
cos(a)+cos(b)
-2sin((a+b)/2)sin((a-b)/2)
cos(a)-cos(b)
(cos(a-b)-cos(a+b))/2
sin(a)sin(b)
(cos(a-b)+cos(a+b))/2
cos(a)cos(b)
(sin(a+b)+sin(a-b))/2
sin(a)cos(b)