If $f(x)=x+\frac{1}{x}$. Which of the following is not a correct option ? |
local minimum value = 2 local maximum value =-2, local minimum value =0 extreme occurs at 1, -1 local maximum value =-2 |
local maximum value =-2, local minimum value =0 |
$f(x)=x+\frac{1}{x},\;x\ne0.$ $f'(x)=1-\frac{1}{x^2}.$ $f'(x)=0 \Rightarrow x=\pm1.$ $f(1)=2,\;f(-1)=-2.$ $\text{Local minimum value}=2,\;\text{Local maximum value}=-2.$ $\text{Hence extremes occur at }x=1,-1.$ $\text{Local minimum value is not }0.$ $\text{Incorrect option: local maximum value = −2, local minimum value = 0.}$ |