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Class 12 Applications Of Derivatives · Assertion Reason1 Marksassertion_reason

Class 12 Maths · Applications Of Derivatives · Assertion Reason #23

Assertion: For a circle, dA/dr at r=6 cm equals 12π cm²/cm. Reason: The rate of change of circle area with respect to radius is dA/dr, where A=πr².

✅ Step-by-Step Solution

Final Answer: Option (A): Both A and R are true, and R correctly explains A.
  1. Differentiating A=πr² gives dA/dr=2πr, hence 12π at r=6.

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