COMEDK · Maths · 27. Application of Derivatives
Quadrilateral PQRS is inscribed inside a rectangle of dimensions \(10 \mathrm{~cm} \times 8 \mathrm{~cm}\). The value of ' \(x\) ', if the area of the quadrilateral is minimum is
- A 9 cm
- B 4 cm
- C 4.5 cm
- D 6.5 cm
Answer & Solution
Correct Answer
(C) 4.5 cm
Step-by-step Solution
Detailed explanation
Let the rectangle be \(ABCD\) with \(AB = CD = 10\) cm and \(AD = BC = 8\) cm. Let \(AQ = x\), \(BR = x\), \(CS = x\), and \(DP = x\). The points are located as follows: \(Q\) is on \(AB\) such that \(AQ = x\), so \(QB = 10 - x\). \(R\) is on \(BC\) such that \(BR = x\), so…
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