हिंदी

A ball is thrown in the air. Its height at any time t is given by h = 3 + 14t – 5t2 . Find the maximum height it can reach.

Advertisements
Advertisements

प्रश्न

A ball is thrown in the air. Its height at any time t is given by h = 3 + 14t – 5t2. Find the maximum height it can reach.

योग
Advertisements

उत्तर

The height h at any t is given by h = 3 + 14t – 5t2 

∴ `"dh"/dt = d/dt(3 + 14t - 5t^2)`

= 0 + 14 x 1 – 5 x 2t

= 14 – 10t

and `(d^2h)/(dt^2) = d/dt(14 - 10t)`

= 0 – 10 x 1

= – 10

The root of `"dh"/dt` = 0,

i.e. 14 – 10t = 0 is t = `(14)/(10) = (7)/(5)`
and
`((d^2h)/(dt^2))_("at" t = 7/5)` = −10 < 0

∴ By the second derivative test, h is maximum at t = `(7)/(5)`.

∴ Maximum height = `(3 + 14t  – 5t^2)_("at" t = 7/5)`

= `3 + 14(7/5) - 5(7/5)^2`

= `3 + (98)/(5) - (245)/(25)`

= `(75 + 490 - 245)/(25)`

= `(320)/(25)`

= 12.8

Hence, the maximum height the ball can reach = 12.8 units.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 2: Applications of Derivatives - Exercise 2.4 [पृष्ठ ९०]

APPEARS IN

बालभारती Mathematics and Statistics 2 (Arts and Science) [English] Standard 12 Maharashtra State Board
अध्याय 2 Applications of Derivatives
Exercise 2.4 | Q 13 | पृष्ठ ९०

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

Show that the height of the cylinder of maximum volume, that can be inscribed in a sphere of radius R is `(2R)/sqrt3.`  Also, find the maximum volume.


If the sum of lengths of hypotenuse and a side of a right angled triangle is given, show that area of triangle is maximum, when the angle between them is π/3.


Show that the altitude of the right circular cone of maximum volume that can be inscribed in a sphere of radius r is `(4r)/3`. Also find maximum volume in terms of volume of the sphere


Find the maximum and minimum value, if any, of the following function given by g(x) = x3 + 1.


Find the maximum and minimum value, if any, of the following function given by h(x) = x + 1, x ∈ (−1, 1)


Find the local maxima and local minima, if any, of the following function. Find also the local maximum and the local minimum values, as the case may be:

g(x) = x3 − 3x


Find the local maxima and local minima, if any, of the following function. Find also the local maximum and the local minimum values, as the case may be:

f(x) = sinx − cos x, 0 < x < 2π


Prove that the following function do not have maxima or minima:

g(x) = logx


Prove that the following function do not have maxima or minima:

h(x) = x3 + x2 + x + 1


It is given that at x = 1, the function x4− 62x2 + ax + 9 attains its maximum value, on the interval [0, 2]. Find the value of a.


Show that of all the rectangles inscribed in a given fixed circle, the square has the maximum area.


For all real values of x, the minimum value of `(1 - x + x^2)/(1+x+x^2)` is ______.


Find the maximum area of an isosceles triangle inscribed in the ellipse  `x^2/ a^2 + y^2/b^2 = 1` with its vertex at one end of the major axis.


A window is in the form of a rectangle surmounted by a semicircular opening. The total perimeter of the window is 10 m. Find the dimensions of the window to admit maximum light through the whole opening


A point on the hypotenuse of a triangle is at distance a and b from the sides of the triangle.

Show that the minimum length of the hypotenuse is `(a^(2/3) + b^(2/3))^(3/2).`


Find the maximum and minimum of the following functions : f(x) = x3 – 9x2 + 24x


Find the maximum and minimum of the following functions : f(x) = `x^2 + (16)/x^2`


Solve the following : An open box with a square base is to be made out of given quantity of sheet of area a2. Show that the maximum volume of the box is `a^3/(6sqrt(3)`.


Solve the following :  A window is in the form of a rectangle surmounted by a semicircle. If the perimeter be 30 m, find the dimensions so that the greatest possible amount of light may be admitted.


Determine the maximum and minimum value of the following function.

f(x) = x log x


Divide the number 20 into two parts such that their product is maximum.


A metal wire of  36 cm length is bent to form a rectangle. Find its dimensions when its area is maximum.


Max value of z equals 3x + 2y subject to x + y ≤ 3, x ≤ 2, -2x + y ≤ 1, x ≥ 0, y ≥ 0 is ______ 


If R is the circum radius of Δ ABC, then A(Δ ABC) = ______.


The minimum value of the function f(x) = 13 - 14x + 9x2 is ______


An open box with square base is to be made of a given quantity of cardboard of area c2. Show that the maximum volume of the box is `"c"^3/(6sqrt(3))` cubic units


Find the dimensions of the rectangle of perimeter 36 cm which will sweep out a volume as large as possible, when revolved about one of its sides. Also, find the maximum volume.


AB is a diameter of a circle and C is any point on the circle. Show that the area of ∆ABC is maximum, when it is isosceles.


The maximum value of `(1/x)^x` is ______.


The function f(x) = x5 - 5x4 + 5x3 - 1 has ____________.


Find the height of the cylinder of maximum volume that can be inscribed in a sphere of radius a.


The area of a right-angled triangle of the given hypotenuse is maximum when the triangle is ____________.


The combined resistance R of two resistors R1 and R2 (R1, R2 > 0) is given by `1/"R" = 1/"R"_1 + 1/"R"_2`. If R1 + R2 = C (a constant), then maximum resistance R is obtained if ____________.


Range of projectile will be maximum when angle of projectile is


Divide 20 into two ports, so that their product is maximum.


Read the following passage and answer the questions given below.


The temperature of a person during an intestinal illness is given by f(x) = 0.1x2 + mx + 98.6, 0 ≤ x ≤ 12, m being a constant, where f(x) is the temperature in °F at x days.

  1. Is the function differentiable in the interval (0, 12)? Justify your answer.
  2. If 6 is the critical point of the function, then find the value of the constant m.
  3. Find the intervals in which the function is strictly increasing/strictly decreasing.
    OR
    Find the points of local maximum/local minimum, if any, in the interval (0, 12) as well as the points of absolute maximum/absolute minimum in the interval [0, 12]. Also, find the corresponding local maximum/local minimum and the absolute ‘maximum/absolute minimum values of the function.

The range of a ∈ R for which the function f(x) = `(4a - 3)(x + log_e5) + 2(a - 7)cot(x/2)sin^2(x/2), x ≠ 2nπ, n∈N` has critical points, is ______.


The function g(x) = `(f(x))/x`, x ≠ 0 has an extreme value when ______.


The maximum distance from origin of a point on the curve x = `a sin t - b sin((at)/b)`, y = `a cos t - b cos((at)/b)`, both a, b > 0 is ______.


The maximum value of f(x) = `logx/x (x ≠ 0, x ≠ 1)` is ______.


A straight line is drawn through the point P(3, 4) meeting the positive direction of coordinate axes at the points A and B. If O is the origin, then minimum area of ΔOAB is equal to ______.


The point in the interval [0, 2π], where f(x) = ex sin x has maximum slope, is ______.


Read the following passage:

Engine displacement is the measure of the cylinder volume swept by all the pistons of a piston engine. The piston moves inside the cylinder bore.

One complete of a four-cylinder four-stroke engine. The volume displace is marked
The cylinder bore in the form of circular cylinder open at the top is to be made from a metal sheet of area 75π cm2.

Based on the above information, answer the following questions:

  1. If the radius of cylinder is r cm and height is h cm, then write the volume V of cylinder in terms of radius r. (1)
  2. Find `(dV)/(dr)`. (1)
  3. (a) Find the radius of cylinder when its volume is maximum. (2)
    OR
    (b) For maximum volume, h > r. State true or false and justify. (2)

Find the maximum profit that a company can make, if the profit function is given by P(x) = 72 + 42x – x2, where x is the number of units and P is the profit in rupees.


Mrs. Roy designs a window in her son’s study room so that the room gets maximum sunlight. She designs the window in the shape of a rectangle surmounted by an equilateral triangle. If the perimeter of the window is 12 m, find the dimensions of the window that will admit maximum sunlight into the room.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×