A. 2a
B. 2√a
C. 2a/√3
D. a/√3
A stone is dropped into a quiet pond and waves move in circles outward from the place where it strikes, at a speed of 30 cm per second. At the instant when the radius of the wave ring is 50 mt, the rate increase in the circumference of the wave ring is
The angle A ofABC is found by measurement to be 630 an the area is calculated by the formula 1/2bc sin A. the percentage error in the calculated value of the area due to an error of 15 minutes in the measured value of A is
A line segment of length 10 cm is divided into two parts and a rectangle is formed with these as adjacent sides, then the dimensions of the rectangle in order that its area is maximum is
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Water is being poured into the inverted conical vessel at the rate of 1.5 cubic meter per minute. Its depth is always equal to twice its radius. The level of water is rising at the rate of 3/8π meter per minute when its depth is
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The sum of three numbers is 30. The first plus three times the second plus four times the third add on to 80. The numbers so that the product of all three is as large as possible are
If the tangent at θ=π/4 to the curve x=a cos3θ, y= a sin3θ meets the x and y axis in A and B, then the length of AB is