Trigonometry-concepts-Relations-Formulae-identities-theorems

Trigonometry basic and advance concepts, Relations, Rules, Formulae, identities, theorems

What is trigonometry definition  

Trigonometry (from Greek "tri" meaning three, "gon" meaning side and metron meaning measure) is a branch of mathematics that studies relationships between side lengths and angles of triangles.

Trigonometry uses & trigonometry  practical applications. 

Trigonometry has been applied in area such as Engineering, surveying, navigation, mechanics, geodesy, construction.

Trigonometric ratios 

Trigonometric ratio help in finding the missing angles and sides of triangle.

trigonometric ratios are ratio between sides of  

Let us take a Right Angle triangle as ABC

• Trigonometry Addition Formulae &  Trigonometry Subtraction Formulae

sin(A+B)   =   sinA.cosB + cosA.sinB

sin(A−B)   =   sinA.cosB − cosA.sinB

cos(A+B)  =   cosA.cosB − sinA.sinB

cos(A−B)  =   cosA.cosB + sinA.sinB

 

    

      tan(A+B)=1 − tanAtanBtanA + tanB​ ​

      tan(A−B)=1 + tanAtanBtanA − tanB​​

     cot(A±B)=cotAcotB ± 1cotAcotB ∓ 1​​

      tan(4π​±θ)=1 ∓ tanθ1 ± tanθ​ ​

      cot(4π​±θ)=cotθ ± 1cotθ ∓ 1​​

       

• Trigonometry Multiple & Trigonometry Submultiple Angle Formulae

          ​sin2θ  =2sinθcosθ

                  

                          =1+tan2θ2tanθ

                            

       cos2θ   =cos2θ−sin2θ

                   =2cos2θ−1                   =1−2sin2θ                   =1+tan2θ1−tan2θ​

           

     


        tan2θ  =1−tan2θ2tanθ​


  

      cos3θ  =4cos3θ−3cosθ






























        sin3θ  =3sinθ−4sin3θ         

         sin3θ  =43sinθ−sin3θ​

        tan3θ  =1−3tan2θ

3tanθ−tan3θ​

           cos3θ  =43cosθ + cos 3θ​

• Trigonometry Identities Formulae

         sin2θ+cos2θ  =1         1+tan2θ         =sec2θ         1+cot2θ         =cosec2θ

• Trigonometric Relations Formulae

           tanθ       =cos θ sin θ 

          cot θ       =sin θ cos θ 

          cot θ       =tan θ 1 

        cosec θ  =sin θ 1 

        sec θ       =cos θ 1 

• Table of Trigonometric Ratios or Trigonometry ratios  tables 

        trigonometry table download 

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