What is the reciprocal function for \( \cos \theta \) ?

The reciprocal function for \( \cos \theta \) is \( \sec \theta \). This means that wherever you see \( \cos \theta \), you can flip it to get \( \sec \theta \), which equals \( \frac{1}{\cos \theta} \). So, when \( \cos \theta \) is positive, \( \sec \theta \) is also positive, and when \( \cos \theta \) approaches zero, \( \sec \theta \) approaches infinity—definitely something to keep in mind! In the world of trigonometry, understanding reciprocal functions can help simplify complex equations. For example, if you're solving a right triangle problem and have the cosine value, you can use \( \sec \theta \) to easily find other ratios, especially if you're working with angles in different quadrants. So, always remember: if you know one, you can easily find the other!