Trig Identities Flashcards
what is the reciprocal of sin x ?
1/cosec x
what it the reciprocal of cos x ?
1/sec x
what is the reciprocal of tan x ?
1/cot x
what it the reciprocal of cosec x ?
1/ sin x
what it the reciprocal of sec x ?
1/ cos x
what is the reciprocal of cot x ?
1/ tan x
what is tan x in terms of sin and cos?
sin x / cos x
what is cot x in terms of sin and cos?
cos x /sin x
what is 1 in terms of sin x and cos x?
1 = sin^2 x + cos^2 x
what does 1 + tan^2 x equate to
sec^2 x
what does 1 + cot^2 x equate to
cosec^2 x
what is sin (A+B)
sinAcosB+sinBcosA
what is cos (A+B)
cosAcosB-sinAsinB
what is tan(A+B)
tanA+tanB / 1-tanAtanB
what is sin 2x
2sinxcosx
what is cos 2x
cos^2 x -sin^2 x
1-2sin^2 x
2cos^2 x-1
what is tan 2x
2 tan x /1-tan^2 x
how often does sin repeat
every 360 or 180 -x
every 2pie or pie - x
how often does tan repeat
every 180
every pie
how often does cos repeat
-x
every 360
every 2pie
what do we use for small angle identities
cos x = 1- x^2/2
sin x = x
tan x = x
what is the co sine rule
a^2=b^2+c^2-2bc cosA
