Maths Trig. Identities and Equations

Arc Length

s = rθ

Sector Area

A = 1/2 r² θ

Minor Segment

A = 1/2 r² (θ - sinθ)

Major Segment

A = π r² - 1/2 r² (θ - sinθ).

Triangle within circle

A = 1/2 r² sinθ

sec²θ

tan²θ + 1 = sec²θ

cosec²θ

1 + cot²θ = cosec²θ

sin(A+B)

sinAcosB + cosAsinB

cos(A+B)

cosAcosB - sinAsinB

sin(A-B)

sinAcosB - cosAsinB

cos(A-B)

cosAcosB + sinAsinB

tan(A+B)

(tanA + tanB) / (1 - tanAtanB)

tan(A-B)

(tanA - tanB) / (1 + tanAtanB)

sin2θ

2sinθcosθ

cos2θ

cos²θ - sin²θ, 1 - 2sin²θ, 2cos²θ - 1

tan2θ

(2tanθ) / (1 - tan²θ)

sin(x)

x

cos(x)

1 - 1/2x²

tan(x)

x

integral of x^-1

ln(x)