Inverse Trig Equation question (1 Viewer)

[DumbPotato123]

How do you solve this equation? I'm absolutely clueless and nothing I've tried has worked so far. The textbook answer is -0.47 (2d.p.) however when you sub it into x it returns −3309.00847.

Thanks in advanced.

 

[erucibon]

Firstly, you have it in degrees - radians gives -1
Now, change cos^-1x into pi/2 - sin^-1x, expand, rearrange for quadratic, solve, taking the negative solution gives -0.486 (3dp)

 

[DumbPotato123]

Firstly, you have it in degrees - radians gives -1
Now, change cos^-1x into pi/2 - sin^-1x, expand, rearrange for quadratic, solve, taking the negative solution gives -0.486 (3dp)

This was one of the first things I tried, I'm pretty sure it's incorrect though. I checked on desmos which shows the solution to be -0.4672. Did forget about radians though .

 

[erucibon]

This was one of the first things I tried, I'm pretty sure it's incorrect though. I checked on desmos which shows the solution to be -0.4672. Did forget about radians though .

My bad, I just forgot to sin it as that is sin^-1x= -.486 from quadratic, this will now give -.467

 

[DumbPotato123]

My bad, I just forgot to sin it as that is sin^-1x= -.486 from quadratic, this will now give -.467

Ooohhhh I see now! Thanks!