Things to Know

sin(π/6)

1/2

sin(30°)

1/2

cos(π/6)

√3/2

cos(30°)

√3/2

sin(0)

0

cos(0)

1

tan(0)

0

sin(2x)

2sinxcosx

cos(2x)

cos²x-sin²x = 1-2sin²x

cos²x

1-sin²x

sin²x

1-cos²x

sin²x+cos²x

1

tan²x+1

sec²x

cot²x+1

csc²x

reciprocal of sine

csc

reciprocal of cosine

sec

reciprocal of tangent

cot

trig function coordinate y

sin

trig function coordinate x

cos

trig function coordinate y/x

tan

sin(-x)

-sinx

cos(-x)

cosx

ln(xy)

ln(x)+ln(y)

ln(x/y)

ln(x)-ln(y)

ln(x^p)

p ln(x)

lne

1

ln(1)

0

point-slope form of a line

y-y₁=m (x-x₁)

vertical line

x=a

horizontal line

y=a

domain of ln(x)

x>0

domain of 1/x

x≠0

domain of √x (or any EVEN root)

x>=0

(a+b)²

a^²+2ab+b^²

(a-b)²

a²-2ab+b²

a²-b²

(a+b)(a+b)

a³-b³

(a-b)(a²-ab+b²)

a³+b³

(a+b)(a²-ab+b²)

tan(π/6)

√3/3

sin(π/4)

√2/2

cos(π/4)

√2/2

tan(π/4)

1

sin(π/3)

√3/2

cos(π/3)

1/2

tan(π/3)

√3

sin(π/2)

1

cos(π/2)

0

tan(π/2)

undefined

sin(π)

0

cos(π)

-1

tan(π)

0

sin(3π/2)

-1

cos(3π/2)

0

tan(3π/2)

undefined

sin(45°)

√2/2

cos(45°)

√2/2

tan(45°)

1

sin(60°)

√3/2

cos(60°)

1/2

tan(60°)

√3

sin(90°)

1

cos(90°)

0

tan(90°)

undefined

sin(180°)

0

cos(180°)

-1

tan(180°)

0

sin(270°)

-1

cos(270°)

0

tan(270°)

undefined