मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी वाणिज्य (इंग्रजी माध्यम) इयत्ता १२ वी

Show that the function f(x) = x-2x+1, x ≠ – 1 is increasing - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

Show that the function f(x) = `(x - 2)/(x + 1)`, x ≠ – 1 is increasing

बेरीज

उत्तर

f(x) = `(x - 2)/(x + 1)` for x ≠ – 1

For function to be increasing, f'(x) > 0

Then, f'(x) = `((x + 1)"d"/("d"x)(x - 2) - (x - 2)"d"/("d"x)(x + 1))/(x + 1)^2`

= `((x + 1) - (x - 2))/(x + 1)^2`

= `(x + 1 - x + 2)/(x + 1)^2`

= `3/(x + 1)^2 > 0`      .......[∵ (x + 1) ≠ 0, (x + 1)2 > 0]

Thus, f(x) is an increasing function for x ≠ – 1.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 1.4: Applications of Derivatives - Q.4

व्हिडिओ ट्यूटोरियलVIEW ALL [3]

संबंधित प्रश्‍न

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


Find the value(s) of x for which y = [x(x − 2)]2 is an increasing function.


Test whether the function is increasing or decreasing. 

f(x) = `"x" -1/"x"`, x ∈ R, x ≠ 0, 


Find the intervals in which the following functions are strictly increasing or decreasing:

10 − 6x − 2x2


Prove that the function f given by f(x) = x2 − x + 1 is neither strictly increasing nor strictly decreasing on (−1, 1).


Which of the following functions are strictly decreasing on `(0, pi/2)`?

  1. cos x
  2. cos 2x
  3. cos 3x
  4. tan x

Find the interval in which the following function are increasing or decreasing  f(x) = x2 + 2x − 5  ?


Find the interval in which the following function are increasing or decreasing \[f\left( x \right) = \left\{ x(x - 2) \right\}^2\] ?


Find the interval in which the following function are increasing or decreasing \[f\left( x \right) = \log\left( 2 + x \right) - \frac{2x}{2 + x}, x \in R\] ?


Show that f(x) = tan−1 (sin x + cos x) is a decreasing function on the interval (π/4, π/2) ?


Show that f(x) = sin x − cos x is an increasing function on (−π/4, π/4) ?


Find the values of 'a' for which the function f(x) = sin x − ax + 4 is increasing function on R ?


Write the set of values of a for which the function f(x) = ax + b is decreasing for all x ∈ R ?


Write the set of values of a for which f(x) = cos x + a2 x + b is strictly increasing on R ?


The function f(x) = 2 log (x − 2) − x2 + 4x + 1 increases on the interval


If the function f(x) = 2x2 − kx + 5 is increasing on [1, 2], then k lies in the interval


The function \[f\left( x \right) = \log_e \left( x^3 + \sqrt{x^6 + 1} \right)\] is of the following types:


If the function f(x) = 2 tan x + (2a + 1) loge | sec x | + (a − 2) x is increasing on R, then


If x = cos2 θ and y = cot θ then find `dy/dx  at  θ=pi/4` 


Test whether the following functions are increasing or decreasing : f(x) = x3 – 6x2 + 12x – 16, x ∈ R.


Find the values of x for which the following functions are strictly decreasing : f(x) = x3 – 9x2 + 24x + 12


Solve the following:

Find the intervals on which the function f(x) = `x/logx` is increasing and decreasing.


The slope of tangent at any point (a, b) is also called as ______.


Find the values of x such that f(x) = 2x3 – 15x2 – 144x – 7 is decreasing function


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


The values of k for which the function f(x) = kx3 – 6x2 + 12x + 11 may be increasing on R are ______.


The function `1/(1 + x^2)` is increasing in the interval ______ 


Show that f(x) = 2x + cot–1x + `log(sqrt(1 + x^2) - x)` is increasing in R


Let `"f (x) = x – cos x, x" in "R"`, then f is ____________.


In `(0, pi/2),`  the function f (x) = `"x"/"sin x"` is ____________.


2x3 - 6x + 5 is an increasing function, if ____________.


The function f(x) = x3 + 6x2 + (9 + 2k)x + 1 is strictly increasing for all x, if ____________.


Which of the following graph represent the strictly increasing function.


If f(x) = x + cosx – a then ______.


Function f(x) = `log(1 + x) - (2x)/(2 + x)` is monotonically increasing when ______.


The interval in which the function f(x) = 2x3 + 9x2 + 12x – 1 is decreasing is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×