Fundamental Identities
Simplifying Expressions Using Identities
Other Identities
Exact Values from Identities
Ancient History - Exact Values
100
(sin x) / (cos x)
What is tan x?
100
(sec x)(cos x)
What is 1?
100

tan(90-x)

What is cot x?

100

cos 15

What is (sqrt6 + sqrt2)/4 ?

100
11pi/6 radians
What is 330 degrees?
200

1 / (csc x)

What is sin x?

200
(tan x)(cos x)
What is sin x?
200

sin (X - Y)

What is sin X cos Y - cos X sin Y ?
200

sin 255

What is (-sqrt6 - sqrt2)/4?

200

sin 60

What is sqrt3/2?

300
cos (-x)
What is cos x?
300
(sec x) / (tan x)
What is csc x?
300

(tan X + tan Y) / (1 - tan X tan Y)

What is tan (X + Y)?

300

tan (23pi/12)

What is -2 + sqrt3?

300

cos (pi/2)

What is 0?
400
sec²x - 1
What is tan²x?
400
sin x (csc x - sec x)
What is 1 - tan x?
400

2 sin X cos X

What is sin (2x)?

400

cos 108 cos 63 + sin 108 sin 63

What is sqrt2/2?

400
tan 135
What is -1?
500
(1 + csc x)(1 - csc x)
What is -cot²x ?
500
csc x - sin x
What is (cos²x) / (sin x) or (cos x)(cot x) ?
500

1 - 2 sin^2 x

What is cos (2x)?

500

(2 tan 105) / (1 - tan^2 105)

What is sqrt3/3?

500

sec 240

What is -2?

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