To solve the inequality \(\sec^{-1}(x) \geq \frac{\pi}{4}\), we first need to understand what \(\sec^{-1}(x)\) represents. The secant inverse function, \(\sec^{-1}(x)\), gives us the angle whose secant is \(x\).
Understanding the Secant Function
The secant function is defined as:
- \(\sec(\theta) = \frac{1}{\cos(\theta)}\)
This means that \(\sec^{-1}(x)\) is defined for \(x \leq -1\) or \(x \geq 1\). The range of \(\sec^{-1}(x)\) is from \(0\) to \(\frac{\pi}{2}\) and from \(\frac{\pi}{2}\) to \(\pi\).
Finding the Values of x
Next, we need to determine when \(\sec^{-1}(x) \geq \frac{\pi}{4}\). The angle \(\frac{\pi}{4}\) corresponds to a secant value of:
- \(\sec\left(\frac{\pi}{4}\right) = \sqrt{2}\)
Thus, the inequality \(\sec^{-1}(x) \geq \frac{\pi}{4}\) translates to:
- \(x \leq -\sqrt{2}\) or \(x \geq \sqrt{2}\)
Final Answer
In conclusion, the solution to the inequality \(\sec^{-1}(x) \geq \frac{\pi}{4}\) is: