Mathbee CBSE Mathbee · CBSE Class 12 Maths
Class 12 Integrals · Long Answer3 Marksindefinite_integration

Class 12 Maths · Integrals · Long Answer #164

Evaluate \(\int \frac{1 - \cos{\left(x \right)}}{\left(\cos{\left(x \right)} + 1\right) \cos{\left(x \right)}}\,dx\). Work on each connected open interval where the real integrand is defined.

✅ Step-by-Step Solution

Final Answer: \(\log{\left(\left|{\tan{\left(x \right)} + \sec{\left(x \right)}}\right| \right)} - 2 \tan{\left(\frac{x}{2} \right)}\) + C
  1. Decompose (1−cos x)/[cos x(1+cos x)]=sec x−2/(1+cos x).
  2. Use 1+cos x=2cos²(x/2), so the second term is −sec²(x/2).
  3. Integrate sec x to ln|sec x+tan x| and −sec²(x/2) to −2tan(x/2).
  4. Therefore the required integral is \(\log{\left(\left|{\tan{\left(x \right)} + \sec{\left(x \right)}}\right| \right)} - 2 \tan{\left(\frac{x}{2} \right)}\) + C.

📋 CBSE Stepwise Marking Scheme

  • [0.5 marks] Decompose (1−cos x)/[cos x(1+cos x)]=sec x−2/(1+cos x).
  • [1 mark] Use 1+cos x=2cos²(x/2), so the second term is −sec²(x/2).
  • [1 mark] Integrate sec x to ln|sec x+tan x| and −sec²(x/2) to −2tan(x/2).
  • [0.5 marks] Therefore the required integral is \(\log{\left(\left|{\tan{\left(x \right)} + \sec{\left(x \right)}}\right| \right)} - 2 \tan{\left(\frac{x}{2} \right)}\) + C.

Master Chapter 7: Integrals

Practise interactive questions, flashcards, visual mind maps, and timed board tests for Integrals.
📘 Chapter Notes & All Exercises 🚀 Open Interactive Workspace →
← Previous Question
Evaluate \(\int e^{2 x} \sin{\left(3 x + 1 \right)}\,dx\). Work on…
Next Question →
Evaluate \(\int \frac{\sin{\left(2 x…

More Practice Questions in Integrals

Related Questions in Integrals