click below
click below
Normal Size Small Size show me how
preap precalculus
trig identities
Question | Answer |
---|---|
sinx | 1/cscx |
cosx | 1/secx |
sin^2x + cos^2x | 1 |
tan^2x + 1 | sec^2x |
1 + cot^2x | csc^2x |
sin(-x) | -sinx [odd] |
csc(-x) | -cscx [odd] |
cos(-x) | cosx [even] |
sec(-x) | secx [even] |
tan(-x) | -tanx [odd] |
cot(-x) | -cotx [odd] |
sinx (cofunction) | cos(pi/2 - x) |
tanx (cofunction) | cot(pi/2 - x) |
secx (cofunction) | csc(pi/2 - x) |
sin(x+y) | sinxcosy + cosxsiny |
sin(x-y) | sinxcosy - cosxsiny |
cos(x+y) | cosxcosy - sinxsiny |
cos(x-y) | cosxcosy + sinxsiny |
tan(x+y) | (tanx + tany)/(1 - tanxtany) OR sin(x+y)/cos(x+y) |
tan(x-y) | (tanx - tany)/(1 + tanxtany) OR sin(x-y)/cos(x-y) |
sin2x | 2sinxcosx |
cos2x | cos^2x - sin^2x OR 2cos^x - 1 OR 1 - 2sin^2x |
tan2x | 2tanx/(1 - tan^2x) OR sin2x/cos2x |
sin(x/2) | +-sqrt (1-cosx)/2 |
cos(x/2) | +-sqrt (1+cosx)/2 |
tan(x/2) | (1-cosx)/sinx OR sinx/(1+cosx) |
sin^2a | (1-cos2a)/2 |
cos^2a | (1+cos2a)/2 |
tan^2a | sin^2a/cos^2a OR (1-cos2a)/(1+cos2a) |