Verified Answer :

we are asked to evaluate the expression sin-1(-0.5). The answer is an angle with units of degrees or radians. In this case, we use a calculator to evaluate the expression. The answer is -30 degrees or negative pi/6. The angle is valid in the third and fourth quadrants

Answer:   \(\dfrac{-\pi}{6}\)

Step-by-step explanation:

To find : The exact value of \(\sin^{-1}(-0.5)\) .

We know that \(\sin^{-1}(\dfrac{1}{2})=\dfrac{\pi}{6}\).

The range of  \(\sin^{-1}(x)\) is between \(\dfrac{-\pi}{2}\text{ and }\dfrac{\pi}{2}\)

Let \(t=\sin^{-1}(-0.5)\)

\(\sin t=-0.5=-\sin(\dfrac{\pi}{6})=\sin(\dfrac{-\pi}{6})\ [\text{Since }}\sin(-x)=-\sin x]\)  

\(\sin(\dfrac{-\pi}{6})=0.5\)

Hence, the principal value of  \(\sin^{-1}(-0.5)=\dfrac{-\pi}{6}\)