Get Answers to all your Questions

header-bg qa

Provide solution for RD Sharma maths class12 Chapter Maxima and Minima exercise Multiple choice question, question 14.

Answers (1)

Answer: \frac{1}{4}

Hint: For local maxima or minima, we must have f'(x)=0.

Given: f(x)=\frac{x}{4-x+x^2}

Solution:

We have,

\begin{aligned} &f(x)=\frac{x}{4-x+x^{2}} \\ &f^{\prime}(x)=\frac{4-x+x^{2}-x(-1+2 x)}{\left(4-x+x^{2}\right)^{2}} \end{aligned}                             

For maxima and minima f'(x)=0

\Rightarrow \frac{4-x+x^{2}-x(-1+2 x)}{\left(4-x+x^{2}\right)^{2}}

\Rightarrow 4-x+x^2-x(-1+2x)=0

\Rightarrow 4-x^2=0

\Rightarrow x^2=4

\Rightarrow x=\pm 2\euro [-1,1]

f(-1)=\frac{-1}{4+1+1}=\frac{-1}{6}

f(1)=\frac{1}{4-1+1}=\frac{1}{4}

Hence, the maximum value is  \frac{1}{4}.

Note: option is not matching with the answer given in the book.

Posted by

infoexpert24

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads