A political party orders an arch for the entrance to the

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A political party orders an arch for the entrance to the ground in which the annual conventions is being held. The profile of the arch follows the equation y = 2x – 0.1x² where y is the height of the arch in meters. The maximum possible height of the arch is

1. 8 meters
2. 10 meters
3. 12 meters
4. 14 meters

Correct Option: B

y = 2x – 0.1x²

	dy	= 2 – 0.2x
	dx

	d²y	< 0
	dx²

Hence maximises at 2 – 0.2x = 0
⇒ x = 10
∴ y = 20 – 10 = 10 m