The distance covered by a particle in t seconds is given by x = 3 + 8t - 4t2. After 1 s its velocity will be
0 unit/s
3 unit/s
4 unit/s
7 unit/s
If the tangent to the parabola y = x(2 - x) at the point (1, 1) intersects the parabola at P. Find the coordinate of P.
The maximum value of xy subject to x + y = 8
8
16
20
24
B.
16
Let p = xy. Given x + y = B y = B - x
Hence, p is maximum for x = 4.
And the maximum value of p is 4 . 4 = 16
A particle moves along a straight line according to the laws = 16- 2t + 3t, where s metres is the distance of the particle from a fixed point at the end of t seconds. The acceleration of the particle at the end of 2s is
36m/s2
34m/s2
36m
None of these
For the curve y = xe, the point
x = - 1 is a point of minimum
x = 0 is a point of minimum
x = - 1 is a point of maximum
x = 0 is a point of maximum
If the slope of the curve at the point (1, 1) is 2, then
a = 1, b = - 2
a = - 1, b = 2
a = 1, b = 2
None of these
If the tangent at (1, 1) on y = x(2 - x)2 meets the curve again at P, then P is
(4, 4)
(- 1, 2)
(9/4, 3/8)
None of these
If there is an error of K % is measuring the edge of a cube, then the per cent error in estimating its volume is
k
3k
None of these