The combination \( \cot \theta + \csc \theta \) always simplifies to \( \cot(\theta/2) \). Keeping these "standard" simplifications in mind makes trigonometric integration much faster.
Step 1: Understanding the Concept:
We simplify the integrand using half-angle or reciprocal identities before integrating. Step 2: Detailed Explanation:
Express the integrand in terms of sine and cosine:
\[ \cot 2x + \csc 2x = \frac{\cos 2x}{\sin 2x} + \frac{1}{\sin 2x} = \frac{1 + \cos 2x}{\sin 2x} \]
Use double-angle identities: \( 1 + \cos 2x = 2\cos^2 x \) and \( \sin 2x = 2\sin x \cos x \).
\[ \frac{2\cos^2 x}{2\sin x \cos x} = \frac{\cos x}{\sin x} = \cot x \]
Now, integrate:
\[ I = \int \cot x dx \]
Using the standard formula for the integral of cotangent:
\[ I = \log_e |\sin x| + C \] Step 3: Final Answer:
The integral is \( \log_e |\sin x| + C \).