Question

How do you find the values of the other five trigonometric functions of the acute angle A with `cosA=2/3`?

Answer 1

If `Cos A = 2/3`
Then, `Sec A = 3/2`
`Sin A` = `√(1-(2/3)^2)` or `(√5)/3`
Then, `Cosec A = 3/(√5)`
So, `Tan A` = `Sin A/Cos A` or `2/(√5)`
Hence, `Cot A` = `(√5)/2`