Trigonometric Identities

Reciprocal Identities:     

• Sin= 1/csc                 

• Cos= 1/sec                    

• Tan= 1/ cot

• Csc= 1/sin                      

• Sec= 1/cos                    

• Cot= 1/tan

Pythagorean Identities: 

• • Sin2 + Cos2 = 1

  • 1 + Tan2 = Sec2

  • 1 + Cot2 = Csc2

Quotient Identities: 

• Tan= Sin/Cos

• Cot= Cos/Sin