The distance of the point on the curve x2 = 2y, which is nearest to the pont (0, 5) is
3
4
None of these
The equation of tangent to the curve 6y = 7 - x3 at (1, 1) is
2x + y = 3
x + 2y = 3
x + y = 1
x + y + 2 = 0
The family of curves in which the sub-tangent at any point to any curve is double the abscissa is given by
x = Cy2
y = Cx2
x2 = Cy2
y2 = Cx2
The sum of two numbers is 20. If the product of the square of one number and cube of the other is maximum, then the numbers are :
12, 8
3, 4
9, 12
15, 18
Gas is being pumped into a spherical balloon at the rate of 30 ft3/min. The rate at which the radius increase when it reaches the value 15ft, is :