Question

Trigonometry identities formulas ​

Answer 1

Answer:

A. Reciprocal identities

a1  sin  A =

1

 csc  A

a4  csc  A =

1

 sin  A

a2  cos  A =

1

 sec  A

a5  sec  A =

1

 cos  A

a3  tan  A =

1

 cot  A

a6  cot  A =

1

 tan  A

B. Ratio identities

b1  tan  A =

 sin  A

 cos  A

b2  cot  A =

 cos  A

 sin  A

C. Opposite Angle identities

c1  sin  ( − A ) = −  sin  A

c2  cos  ( − A ) = c o s A (Caution - not like c1, c3)

c3  tan  ( − A ) = −  tan  A

D. Pythagorean identities

d1  sin  2 A +  cos  2 A = 1

d2 1 +  tan  2 A =  sec  2 A

d3 1 +  cot  2 A =  csc  2 A

E. Complementary angle identities

e1  sin  A =  cos 

π

2

− A

e2  tan  A =  cot 

π

2

− A

e3  sec  A =  csc 

π

2

− A

* Note:

π

2

is 90° in radians.

If A is in degrees, use 90 instead of

π

2

For example:  sin  A =  cos  ( 90 − A ).

HOPE IT WILL HELP U..☺️

Answer 2

[tex]\boxed{

\begin{minipage}{7 cm}

Fundamental Trigonometric Identities \\ \\

$\sin^2\theta + \cos^2\theta=1 \\ \\

1+\tan^2\theta = \sec^2\theta \\ \\

1+\cot^2\theta = \text{cosec}^2 \, \theta$

\end{minipage}

}[/tex]