Twenty meters of wire is available for fencing off a flower-bed in the form of a circular sector. Then the maximum area (in sq. m) of the flower-bed, is :

Question

Accepted Answer

Correct answer: C. (c)2r + λ = 20 ⇒ 2r + rθ = 20 ⇒ θ = 2 0–2 rr A = π r^2θ3 6 0 = r^22. 2 0–2 rr = r(10–r) A = 10r – r^2 d Ad r = 10 – 2r = 0 ⇒ r = 5 ∴ θ = 1 05 = 2

$Twenty meters of wire is available for fencing off a flower-bed in the form of a circular sector. Then the maximum area (in sq. m) of the flower-bed, is :$

Solution

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