😱 Most Students Fail This Trigonometric Identity | Class 11–12 | CBSE | JEE

Описание: (cosx+cosy)^2 + (sinx-siny)^2 =4cos^(x-y/2)
Most students lose marks in exams because they try to prove trigonometric identities in the wrong way 😱

In this short video, we verify the important trigonometric identity step-by-step:

(\cos x + \cos y)^2 + (\sin x - \sin y)^2 = 4\cos^2\left(\frac{x+y}{2}\right)

This question is very important for: • Class 11 Trigonometry
• Class 12 Trigonometry
• CBSE Board Exams
• JEE Main & JEE Advanced
• State Board Exams

📌 Common mistake:
❌ Starting from RHS
✅ Always simplify LHS first

This identity is frequently asked as: ✔ Identify proof
✔ Verify identity
✔ One-step board exam question

👨‍🏫 Explained by Mathematics Sirji with concept clarity so that you never forget this method.

📚 If you are preparing for CBSE Boards 2025–26, JEE Main, JEE Advanced, this short will save your marks!

👉 Watch till the end to understand the hidden trigonometric trick.

👍 Like | 🔔 Subscribe | 💬 Comment “TRIGO” if you want more identity proofs.



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