English

For manufacturing x units, labour cost is 150 – 54x and processing cost is x2. Price of each unit is p = 10800 – 4x2. Find the values of x for which Revenue is increasing.

Advertisements
Advertisements

Question

For manufacturing x units, labour cost is 150 – 54x and processing cost is x2. Price of each unit is p = 10800 – 4x2. Find the values of x for which Revenue is increasing.

Sum
Advertisements

Solution

Revenue = Price × Demand

∴ R = p × x

∴ R = (10800 - 4x2)x

∴ R = 10800x - 4x3

∴ `"dR"/"dx" = 10800 - 12"x"^2`

Since revenue R is an increasing function,

`"dR"/"dx" > 0`

∴ `10800 - 12"x"^2` > 0

∴ 10800 > 12 x2 

∴ `10800/12` > x2

∴ 900 > x2 

∴ x2 < 900

∴ - 30 < x < 30

∴ x > - 30 and x < 30

But x > - 30 is not possible     ....[∵ x > 0]

∴ x < 30

∴ The revenue R is increasing for x < 30.

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Applications of Derivatives - Exercise 4.4 [Page 112]

RELATED QUESTIONS

The amount of pollution content added in air in a city due to x-diesel vehicles is given by P(x) = 0.005x3 + 0.02x2 + 30x. Find the marginal increase in pollution content when 3 diesel vehicles are added and write which value is indicated in the above question.


Find the intervals in which f(x) = sin 3x – cos 3x, 0 < x < π, is strictly increasing or strictly decreasing.


Prove that f(x) = ax + b, where a, b are constants and a > 0 is an increasing function on R ?


Prove that f(x) = ax + b, where a, b are constants and a < 0 is a decreasing function on R ?


Show that f(x) = \[\frac{1}{1 + x^2}\] decreases in the interval [0, ∞) and increases in the interval (−∞, 0] ?


Find the interval in which the following function are increasing or decreasing f(x) = x3 − 6x2 − 36x + 2 ?


Find the interval in which the following function are increasing or decreasing f(x) = 2x3 − 15x2 + 36x + 1 ?


Find the interval in which the following function are increasing or decreasing  f(x) =  \[5 x^\frac{3}{2} - 3 x^\frac{5}{2}\]  x > 0 ?


Show that f(x) = sin x is increasing on (0, π/2) and decreasing on (π/2, π) and neither increasing nor decreasing in (0, π) ?


Show that the function f given by f(x) = 10x is increasing for all x ?


Find the values of b for which the function f(x) = sin x − bx + c is a decreasing function on R ?


Write the set of values of 'a' for which f(x) = loga x is increasing in its domain ?


Find the set of values of 'b' for which f(x) = b (x + cos x) + 4 is decreasing on R ?


The function f(x) = cot−1 x + x increases in the interval


f(x) = 2x − tan−1 x − log \[\left\{ x + \sqrt{x^2 + 1} \right\}\] is monotonically increasing when

 


The function \[f\left( x \right) = \frac{x}{1 + \left| x \right|}\] is 

 


The radius r of a right circular cylinder is increasing uniformly at the rate of 0·3 cm/s and its height h is decreasing at the rate of 0·4 cm/s. When r = 3·5 cm and h = 7 cm, find the rate of change of the curved surface area of the cylinder. \[\left[ \text{ Use } \pi = \frac{22}{7} \right]\]


Prove that y = `(4sinθ)/(2 + cosθ) - θ` is an increasing function if `θ ∈[0, pi/2]`


Find the value of x, such that f(x) is increasing function.

f(x) = 2x3 - 15x2 + 36x + 1 


State whether the following statement is True or False:

The function f(x) = `"x"*"e"^("x" (1 - "x"))` is increasing on `((-1)/2, 1)`.


f(x) = `{{:(0","                 x = 0 ), (x - 3","   x > 0):}` The function f(x) is ______


The function f(x) = sin x + 2x is ______ 


In which interval is the given function, f(x) = 2x3 - 21x2 + 72x + 19 monotonically decreasing?


Prove that the function f(x) = tanx – 4x is strictly decreasing on `((-pi)/3, pi/3)`


The function f (x) = 2 – 3 x is ____________.


The interval in which the function f is given by f(x) = x2 e-x is strictly increasing, is: ____________.


Function given by f(x) = sin x is strictly increasing in.


Function f(x) = x100 + sinx – 1 is increasing for all x ∈ ______.


The interval in which the function f(x) = `(4x^2 + 1)/x` is decreasing is ______.


The function f(x) = xex(1 − x), x ∈ R, is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×