Question

Costheta =12/13, 3pi/2

Answer 1

QUESTION 1

`cos\ \theta = (12)/(13)\\\theta = cos^(-1)(12)/(13) = 22.62\textdegree = 0.3948\ (\text{radians})`

QUESTION 2

`(3\pi)/(2) < \theta < 2\pi\ \text{then find}\ sin(2\theta)`

First, the fact that we have
`sin(2\theta)` means we have to adjust our range

`(3\pi)/(2) < \theta < 2\pi\ \ \text{becomes}\ \ 3\pi < 2\theta < 4\pi\`

`sin\ 2\theta = (3\pi)/(2)\\2\theta = sin^(-1) (3\pi)/(2)\\2\theta = \text{error}`

There are no solutions to inverse sin of
`(3\pi)/(2)\\`