Locate and bisect a circular-equation root
Consider the circular equation shown below
\[\sin x=-0.125x + 0.582\]
Write the algebraic function in the equation as \(P(x)=-0.125x + 0.582\)
Let \(F(x)\) be the circular side minus the algebraic side, so \(F(x)=\sin x-\left(-0.125x + 0.582\right)\)
The sign-changing interval under consideration is \(\left[\frac{3}{10},\frac{9}{10}\right]\). The table also gives one point just outside each endpoint
| \(x\) | \(F(x)\) |
|---|---|
| \(\frac{3}{20}\) | \(\approx -0.414\) |
| \(\frac{3}{10}\) | \(\approx -0.249\) |
| \(\frac{9}{10}\) | \(\approx 0.314\) |
| \(\frac{21}{20}\) | \(\approx 0.417\) |
Use the endpoint signs in the table to identify what can be concluded about a root
Select the two functions, the justified root count and the interval containing the sign change