Problem 53

Question

Verify each identity. $$\frac{\sin \theta-\cos \theta}{\sin \theta}+\frac{\cos \theta-\sin \theta}{\cos \theta}=2-\sec \theta \csc \theta$$

Step-by-Step Solution

Verified
Answer
After simplifying the given trigonometric expression, we find that the left-hand side (LHS) matches with the right-hand side (RHS). Therefore, the original equation is a valid trigonometric identity.
1Step 1. Simplify the Left-Hand Side (LHS)
Start by simplifying each of the individual fractions on the left-hand side. The given LHS is \(\frac{\sin \theta-\cos \theta}{\sin \theta}+\frac{\cos \theta-\sin \theta}{\cos \theta}\). This can be rewritten as \(1-\frac{\cos \theta}{\sin \theta} + 1-\frac{\sin \theta}{\cos \theta}\).
2Step 2. Simplify Further
To further simplify, we can replace \(\frac{\cos \theta}{\sin \theta}\) with \(\csc \theta\) and \(\frac{\sin \theta}{\cos \theta}\) with \(\sec \theta\). So, this gives us \(1-\csc \theta + 1-\sec \theta\).
3Step 3. Combine the Terms
Upon combining similar terms we get: \(2-\csc \theta -\sec \theta\) as the simplified Left hand side.
4Step 4. Verify the Identity
After the simplification, we find that the LHS is equal to the RHS. Thus, proving the trigonometric identity.