' k ' is the least positive integer for which the function f ( x )=(2 x +1)50(3 x -4)60 is increasing in [ k , ∞). The value of ' k ' is

Question

' k ' is the least positive integer for which the function f ( x )=(2 x +1)50(3 x -4)60 is increasing in [ k , ∞). The value of ' k ' is (A) 2 (B) 3 (C) 4 (D) 5

Tardigrade Admin · Accepted Answer

Given, f ( x )=(2 x +1)50(3 x -4)60 f prime( x )=220(2 x +1)49 ⋅(3 x -4)59(3 x -1)

Q. ' $k$ ' is the least positive integer for which the function $f (x) = (2 x + 1)^{50} (3 x - 4)^{60}$ is increasing in $[k, \infty)$ . The value of ' $k$ ' is

2

3

4

5

Given, $f (x) = (2 x + 1)^{50} (3 x - 4)^{60}$
$f^{'} (x) = 220 (2 x + 1)^{49} \cdot (3 x - 4)^{59} (3 x - 1)$

Q. ' k ' is the least positive integer for which the function f(x)=(2x+1)50(3x−4)60 is increasing in [k,∞). The value of ' k ' is

2

3

4

5

Given, f(x)=(2x+1)50(3x−4)60 f′(x)=220(2x+1)49⋅(3x−4)59(3x−1)

Q. ' $k$ ' is the least positive integer for which the function $f (x) = (2 x + 1)^{50} (3 x - 4)^{60}$ is increasing in $[k, \infty)$ . The value of ' $k$ ' is

Given, $f (x) = (2 x + 1)^{50} (3 x - 4)^{60}$
$f^{'} (x) = 220 (2 x + 1)^{49} \cdot (3 x - 4)^{59} (3 x - 1)$