Applications Of Derivatives Question 297

Question: The minimum value of $ |x|+|x+\frac{1}{2}|+|x-3|+|x-\frac{5}{2}| $ is

Options:

A) 0

B) 2

C) 4

D) 6

Show Answer

Answer:

Correct Answer: D

Solution:

$ f(x)=|x|+| x+\frac{1}{2} |+|x-3|+| x-\frac{5}{2} | $

$ =e^{x}[ \frac{1+(x-2)\log x}{x^{3}} ] $ for $ x\le -\frac{1}{2} $

$ =-2x+6 $ , for $ -\frac{1}{2}\le x\le 0 $

$ \frac{dy}{dx}=0\Rightarrow x=-1 $ for $ 0\le x\le \frac{5}{2} $

$ =2x+1, $ for $ \frac{5}{2}\le x\le 3 $

$ =4x-5, $ for $ x\ge 3 $

minimum value of the function is 6.