हिंदी

Find all the points of local maxima and local minima of the function f(x) = -34x4-8x3-452x2+105

Advertisements
Advertisements

प्रश्न

Find all the points of local maxima and local minima of the function f(x) = `- 3/4 x^4 - 8x^3 - 45/2 x^2 + 105`

योग
Advertisements

उत्तर

f′(x) = –3x3 – 24x2 – 45x

= – 3x(x2 + 8x + 15)

= – 3x(x + 5)(x + 3)

f′(x) = 0

⇒ x = –5, x = –3, x = 0

f″(x) = –9x2 – 48x – 45

= –3(3x2 + 16x + 15)

f″(0) = – 45 < 0. Therefore, x = 0 is point of local maxima

f″(–3) = 18 > 0. Therefore, x = –3 is point of local minima

f″(–5) = –30 < 0. Therefore x = –5 is point of local maxima.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 6: Application Of Derivatives - Solved Examples [पृष्ठ १२३]

APPEARS IN

एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
अध्याय 6 Application Of Derivatives
Solved Examples | Q 9 | पृष्ठ १२३

वीडियो ट्यूटोरियलVIEW ALL [5]

संबंधित प्रश्न

Find the maximum and minimum value, if any, of the following function given by f(x) = (2x − 1)2 + 3. 


Find the maximum and minimum value, if any, of the following function given by f(x) = −(x − 1)2 + 10 


Find the maximum and minimum value, if any, of the following function given by h(x) = sin(2x) + 5.


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:

`h(x) = sinx + cosx, 0 < x < pi/2`


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


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

`f(x) = xsqrt(1-x), x > 0`


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

h(x) = x3 + x2 + x + 1


Find the maximum value of 2x3 − 24x + 107 in the interval [1, 3]. Find the maximum value of the same function in [−3, −1].


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


A wire of length 28 m is to be cut into two pieces. One of the pieces is to be made into a square and the other into a circle. What should be the length of the two pieces so that the combined area of the square and the circle is minimum?


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


 Find the point on the straight line 2x+3y = 6,  which is closest to the origin. 


Find the maximum and minimum of the following functions : f(x) = `logx/x`


Find the volume of the largest cylinder that can be inscribed in a sphere of radius ‘r’ cm.


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 : Show that the height of a right circular cylinder of greatest volume that can be inscribed in a right circular cone is one-third of that of the cone.


Solve the following : Show that the height of the cylinder of maximum volume that can be inscribed in a sphere of radius R is `(2"R")/sqrt(3)`. Also, find the maximum volume.


A rectangular sheet of paper has it area 24 sq. Meters. The margin at the top and the bottom are 75 cm each and the sides 50 cm each. What are the dimensions of the paper if the area of the printed space is maximum?


If f(x) = px5 + qx4 + 5x3 - 10 has local maximum and minimum at x = 1 and x = 3 respectively then (p, q) = ______.


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


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.


The sum of the surface areas of a rectangular parallelopiped with sides x, 2x and `x/3` and a sphere is given to be constant. Prove that the sum of their volumes is minimum, if x is equal to three times the radius of the sphere. Also find the minimum value of the sum of their volumes.


The curves y = 4x2 + 2x – 8 and y = x3 – x + 13 touch each other at the point ______.


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


Find the area of the largest isosceles triangle having a perimeter of 18 meters.


The function `"f"("x") = "x" + 4/"x"` has ____________.


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


Let x and y be real numbers satisfying the equation x2 – 4x + y2 + 3 = 0. If the maximum and minimum values of x2 + y2 are a and b respectively. Then the numerical value of a – b is ______.


A cone of maximum volume is inscribed in a given sphere. Then the ratio of the height of the cone to the diameter of the sphere is ______.


Let f(x) = |(x – 1)(x2 – 2x – 3)| + x – 3, x ∈ R. If m and M are respectively the number of points of local minimum and local maximum of f in the interval (0, 4), then m + M is equal to ______.


The minimum value of 2sinx + 2cosx is ______.


A rectangle with one side lying along the x-axis is to be inscribed in the closed region of the xy plane bounded by the lines y = 0, y = 3x and y = 30 – 2x. The largest area of such a rectangle is ______.


If f(x) = `1/(4x^2 + 2x + 1); x ∈ R`, then find the maximum value of f(x).


The shortest distance between the line y - x = 1and the curve x = y2 is


For a function defined on an interval \[I\], which condition means that \[f\] has a minimum value at \[c\in I\]?


Which statement gives the meaning of a local minimum at \[c\]?


For \[f(x)=3x^4+4x^3-12x^2+12\], which is the correct factorization of \[f'(x)\]?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×