###
sin(30)

sin(π/6)

√(1/4) = 1/2

###
tan(90)

tan(π/2)

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###
Range of sin^(-1)

(-π/2)≤ sin^(-1)θ ≤ (π/2)

###
Range of cos^(-1)

0 ≤ cos^(-1)θ ≤ π

###
Range of tan^(-1)

(-π/2)≤ tan^(-1)θ ≤ (π/2)

###
(sin x)(csc x) =1

Reciprocal identity

(sin x)(csc x) =1

###
(cos x)(sec x) = 1

Reciprocal identity

(cos x)(sec x) = 1

###
(tan x)(cot x) = 1

reciprocal identity

(tan x)(cot x) = 1

###
sin 2x = (2 sin x)(cos x)

sin 2x = (2 sin x)(cos x)

###
cos 2x = (cos²x) - (sin²x)

cos 2x = (cos²x) - (sin²x)

###
cos 2x = (2 cos²x) -1

cos 2x = (2 cos²x) -1

###
(sin²x) + (cos²x) = 1

(sin²x) + (cos²x) = 1

###
1 + tan²x = sec²x

1 + tan²x = sec²x

###
1 + cot²x = csc²x

1 + cot²x = csc²x

###
(sin(angle))/(opposite side) = constant

Law of Sines

(sin(angle))/(opposite side) = constant

###
a² = b² + c² - 2bc(cos A)

Law of Cosines

a² = b² + c² - 2bc(cos A)

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