NCERT Class 12 · Ch 9 Exercise 9.3 · Q20
NCERT Class 12 Maths · Chapter 9 Differential Equations · Exercise 9.3 Question 20
Continuous growth at r%/year doubles ₹100 in 10 years. Find r, using log 2=0.6931.
💡 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: r=10log 2≈6.931% per year.
- P′=(r/100)P gives P=100e^(rt/100).
- Set P(10)=200: e^(r/10)=2, so r=10log 2.
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