Question

1+1/sin(alpha) =4 the range is for alpha is from 0 to 360 find alpha???

I got the first angle as 19.5, however, the marking scheme stated that there is another angle(160.5) can you please explain how they got the second angle

Answer 1

See below.

Explanation:

We have:

`(sin alpha + 1)/sinalpha = 4`

`sinalpha + 1 = 4sinalpha`

`1 = 3sinalpha`

`sinalpha = 1/3`

`alpha = 19.5 and ?`

We know that sine is positive in the first and second quadrants, thus the reference angle for the second value of alpha is going to be `19.5˚`, or `alpha_2 = 180˚ - 19.5˚ = 160.5˚`.

As required.

Hopefully this helps!