Respuesta :

Answer:

Proof below

Step-by-step explanation:

Trigonometric Identities

We'll prove that:

[tex]\displaystyle \frac{\sin A+\cos A}{\sec A+\csc A}=\sin A*\cos A[/tex]

Recall:

[tex]\displaystyle \sec A =\frac{1}{\cos A}[/tex]

[tex]\displaystyle \csc A =\frac{1}{\sin A}[/tex]

Applying those definitions:

[tex]\displaystyle \frac{\sin A+\cos A}{\sec A+\csc A}=\frac{\sin A+\cos A}{\frac{1}{\cos A}+\frac{1}{\sin A}}[/tex]

Adding the fractions:

[tex]\displaystyle \frac{\sin A+\cos A}{\sec A+\csc A}=\frac{\sin A+\cos A}{\frac{\sin A+\cos A}{\cos A*\sin A}}[/tex]

Dividing the fractions:

[tex]\displaystyle \frac{\sin A+\cos A}{\sec A+\csc A}=(\sin A+\cos A)*\frac{\cos A*\sin A}{\sin A+\cos A}[/tex]

Simplifying:

[tex]\displaystyle \frac{\sin A+\cos A}{\sec A+\csc A}=\cos A*\sin A[/tex]

Hence proved