Question

Given sine of theta equals 3 over 5 and cosine of theta equals 4 over 5 which of the following can be proven using a Pythagorean identity?

Answer 1

The pythagorean theorem is

`c^2=a^2+b^2`

Note that in unit circle, the radius is 1 and it also represents the hypotenuse in a right triangle.

From the problem :

`\sin \theta=(3)/(5)\quad \cos \theta=(4)/(5)`

This will be the a and b in the pythagorean theorem.

It will be :

`((3)/(5))^2+((4)/(5))^2=1`

The answer is B.