Question

Find cos theta if csc theta = square root 5

Answer 1

cos theta = adjacent/hypotenuse =
`(2)/(√(5) )`

Explanation:

csc theta = hypotenuse/opposite =
`√(5)` /1 (reciprocal identity)

1^2 + b^2 =
`√(5)`^2 (pythagorean theorem)

b^2 = 5-1

b = 2

cos theta = adjacent/hypotenuse = 2/
`√(5)` (quotient identity)