Given the sum of the perimeters of a square and a circle, show that the sum of their areas is least when one side of the square is equal to diameter of the circle.

Asked by Aaryan | 1 year ago |  135

1 Answer

Solution :-

Let us say the sum of perimeter of square and circumference of circle be L

Given sum of the perimeters of a square and a circle.

Assuming, side of square = a and radius of circle = r

Then, L = 4a + 2πr

= a = \( \dfrac{ (L – 2πr)}{4}\)… (1)

Let the sum of area of square and circle be S

So, S = a2 + πr2

RD Sharma Solutions for Class 12 Maths Chapter 18 Maxima and Minima Image 34

RD Sharma Solutions for Class 12 Maths Chapter 18 Maxima and Minima Image 35

Answered by Sakshi | 1 year ago

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