Basic Trigonometric Identities



Basic Trigonometric Identities

Fundamental Identities

cos2 ( + sin2 ( = 1

1 + tan2 ( = sec2 (

1 + cot2 ( = csc2 (

sin ( = − sin(−() csc ( = − csc(−()

cos ( = cos(−() sec ( = sec(−()

tan ( = − tan(−() cot ( = − cot(−()

Addition formulas

sin(( + () = sin ( cos ( + cos ( sin (

sin(( − () = sin ( cos ( − cos ( sin (

cos(( + () = cos ( cos ( − sin ( sin (

cos(( − () = cos ( cos ( + sin ( sin (

Double-angle formulas

sin 2( = 2 sin ( cos (

cos 2( = cos2 ( − sin2 ( = 2 cos2 ( − 1 = 1 − 2sin2 (

Half-angle formulas

sin2 ( = (1 − cos 2( )/2

cos2 ( = (1 + cos 2( )/2

Exponential forms*

[pic] [pic]

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download