NCERT Class 12 · Ch 5 Exercise 5.1 · Q21
NCERT Class 12 Maths · Chapter 5 Continuity And Differentiability · Exercise 5.1 Question 21
Discuss continuity of (a) sin x+cos x, (b) sin x−cos x, (c) 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: All three are continuous on R.
- Sine and cosine are continuous everywhere.
- Sums, differences and products of continuous functions are continuous, giving the result for all three expressions.
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