हिंदी

Find the value of x, such that f(x) is increasing function. f(x) = x2 + 2x - 5 - Mathematics and Statistics

Advertisements
Advertisements

प्रश्न

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

f(x) = x2 + 2x - 5 

योग

उत्तर

f(x) = x2 + 2x - 5 

∴ f'(x) = 2x + 2

f(x) is an increasing function, if f'(x) > 0

∴ 2x + 2 > 0

∴ 2x > -2

∴ x > - 1

Thus, f(x) is an increasing function for x > -1, i.e., (-1, ∞)

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Applications of Derivatives - Exercise 4.2 [पृष्ठ १०६]

APPEARS IN

बालभारती Mathematics and Statistics 1 (Commerce) [English] 12 Standard HSC Maharashtra State Board
अध्याय 4 Applications of Derivatives
Exercise 4.2 | Q 2.2 | पृष्ठ १०६

वीडियो ट्यूटोरियलVIEW ALL [3]

संबंधित प्रश्न

Test whether the function is increasing or decreasing. 

f(x) = `"x" -1/"x"`, x ∈ R, x ≠ 0, 


Find the least value of a such that the function f given by f (x) = x2 + ax + 1 is strictly increasing on [1, 2].


Show that the function f(x) = 4x3 - 18x2 + 27x - 7 is always increasing on R.


Find the interval in which the following function are increasing or decreasing   f(x) = 2x3 − 12x2 + 18x + 15 ?


Find the interval in which the following function are increasing or decreasing  f(x) = 5x3 − 15x2 − 120x + 3 ?


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


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 f(x) = x − sin x is increasing for all x ∈ R ?


Show that f(x) = cos x is a decreasing function on (0, π), increasing in (−π, 0) and neither increasing nor decreasing in (−π, π) ?


Show that f(x) = tan x is an increasing function on (−π/2, π/2) ?


Show that the function f(x) = sin (2x + π/4) is decreasing on (3π/8, 5π/8) ?


Show that f(x) = x9 + 4x7 + 11 is an increasing function for all x ∈ R ? 


Prove that the function f(x) = x3 − 6x2 + 12x − 18 is increasing on R ?


State when a function f(x) is said to be increasing on an interval [a, b]. Test whether the function f(x) = x2 − 6x + 3 is increasing on the interval [4, 6] ?


Find the intervals in which f(x) = (x + 2) e−x is increasing or decreasing ?


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


Prove that the following function is increasing on R f \[f\left( x \right) = 4 x^3 - 18 x^2 + 27x - 27\] ?


Find the value(s) of a for which f(x) = x3 − ax is an increasing function on R ?


Find the interval in which f(x) is increasing or decreasing f(x) = x|x|, x \[\in\] R ?


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


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


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

 


If the demand function is D = 50 - 3p - p2, find the elasticity of demand at (a) p = 5 (b) p = 2 ,  Interpret your result. 


Find the intervals in which the function `f("x") = (4sin"x")/(2+cos"x") -"x";0≤"x"≤2pi` is strictly increasing or strictly decreasing. 


Choose the correct option from the given alternatives :

Let f(x) = x3 – 6x2 + 9x + 18, then f(x) is strictly decreasing in ______.


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

f(x) = 2x3 - 15x2 - 144x - 7 


Find the values of x for which f(x) = 2x3 – 15x2 – 144x – 7 is

(a) Strictly increasing
(b) strictly decreasing


Determine for which values of x, the function y = `x^4 – (4x^3)/3` is increasing and for which values, it is decreasing.


The function f(x) = tanx – x ______.


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


If f(x) = sin x – cos x, then interval in which function is decreasing in 0 ≤ x ≤ 2 π, is:


The function f: N → N, where

f(n) = `{{:(1/2(n + 1), "If n is sold"),(1/2n, "if n is even"):}` is


Show that function f(x) = tan x is increasing in `(0, π/2)`.


State whether the following statement is true or false.

If f'(x) > 0 for all x ∈ (a, b) then f(x) is decreasing function in the interval (a, b).


Let 'a' be a real number such that the function f(x) = ax2 + 6x – 15, x ∈ R is increasing in `(-∞, 3/4)` and decreasing in `(3/4, ∞)`. Then the function g(x) = ax2 – 6x + 15, x∈R has a ______.


Let f(x) be a function such that; f'(x) = log1/3(log3(sinx + a)) (where a ∈ R). If f(x) is decreasing for all real values of x then the exhaustive solution set of a is ______.


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


The function f(x) = tan–1(sin x + cos x) is an increasing function in ______.


A function f is said to be increasing at a point c if ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×