NCERT Class 12 · Ch 6 Exercise 6.3 · Q9
NCERT Class 12 Maths · Chapter 6 Applications Of Derivatives · Exercise 6.3 Question 9
Find the maximum of sin x+cos x.
💡 Concept Hints
- Identify the domain and the inner and outer functions, or the relevant one-sided limits.
- Apply the appropriate differentiation or limit rule, keep all chain factors, and check exceptional points.
✅ Step-by-Step Solution
Final Answer: √2, attained at x=π/4+2nπ.
- Rewrite sin x+cos x=√2 sin(x+π/4).
- Sine is at most 1 and reaches 1 at x+π/4=π/2+2nπ.
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