Question

How do you find Sin(ø) if Sec(ø)= -10/7, ø is in quadrant 3?

Answer 1

`sqrt51/10`

Explanation:

`sec t = 1/(cos t) = - 10/7`
`cos t = - 7/10`
`sin^2 t = 1 - cos^2 t = 1 - 49/100 = 51/100`
`sin t = +- sqrt51/10`
Since t is in Quadrant III, sin t is positive.
`sin t = sqrt51/10`