Question

Given Cos theta 2/3 and sin theta < 0 what would be sin theta and cot theta?

Its about pythagorean identities

Answer 1

Step 1:

The trigonometric function is and .

is positive and is negative means lies in fourth quadrant .

In fourth quadrant, all trigonometric functions  except and are negative.

Pythagorean identities is .

Substitute in above formula.

Since , .

Step 2:

Reciprocal identity: .

Substitute in above formula.

Pythagorean identity is

Substitute in above formula.

in fourth quadrant , .

Solution:

and .