Question

If I have a triangle where `cos u = -5/7` and `sin u >0`, how do I find the sine, tangent, cotangent, secant, and cosecant of the angle u?

Answer 1

`cos u = -5/7`
`sin^2 u = 1 - cos^2 u = 1 - 25/49 = 24/49`
`sin u = (2sqrt6)/7`
`tan u = sin/(cos) = ((2sqrt6)/7)(-7/5) = - (2sqrt6)/5`
`cot u = 1/(tan) = - 5/(2sqrt6) = - (5sqrt6)/12`
`sec u = 1/(cos) = - 7/5`
`csc u = 1/(sin) = 7/(2sqrt6) = (7sqrt6)/12`