Question

How do you solve `Sin (3 theta) = -1`?

Answer 1

`S={90^@ +120^@ n}`

Explanation:

`3theta=sin^-1(-1)`

`3theta=270^@ +360^@ n`

`theta=270^@ xx 1/3 +360^@ n xx 1/3`

`theta=90^@ +120^@ n`

`S={90^@ +120^@ n}`