How to get 2 angle values for an asin?

Hey guys, I'm trying to solve for 2 angles that have the same sine value.

i.e. if x = asin(0.5), then x could be 30 degrees or 150 degrees.

I can't get this to come out though.

tried declaring a 1x2 symbolic variable x: [x1,x2], but if I try:

S = solve('x = asin(0.5)',x)

Then what I get out is:

x = 0.52... (30 degrees)
x1 = 0
x2 = 0

Can anyone help me out here? What am I doing wrong?

Thanks,

Joshua

Answer 1

[A Jenkins]

>> syms x
>> solve('0.5 = sin(x)',x)

ans =

   0.52359877559829887307710723054658
    2.6179938779914943653855361527329

[Joshua D'Agostino]

Oh I see, I'm doing it the wrong way around. Thanks bud! Any idea why it doesn't work doing it the way I initially had it though?

[A Jenkins]

arcsin is defined to only return the principal value. The documentation says:

For real elements of x in the interval [-1,1], asin(x) returns values in the interval [-pi/2,pi/2]. For real elements of x outside the interval [-1,1] and for complex values of x, asin(x) returns complex values.

[Joshua D'Agostino]

Oh I see. Gotcha, cheers mate