Question and Answers Forum

All Questions      Topic List

Limits Questions

Previous in All Question      Next in All Question      

Previous in Limits      Next in Limits      

Question Number 182797 by universe last updated on 14/Dec/22

 find  the max and  min value   f(x,y,z) = x^3 +y^3 +z^3 −9xy−9xz+27x

$$\:\mathrm{find}\:\:\mathrm{the}\:\mathrm{max}\:\mathrm{and}\:\:\mathrm{min}\:\mathrm{value} \\ $$$$\:\mathrm{f}\left(\mathrm{x},\mathrm{y},\mathrm{z}\right)\:=\:\mathrm{x}^{\mathrm{3}} +\mathrm{y}^{\mathrm{3}} +\mathrm{z}^{\mathrm{3}} −\mathrm{9xy}−\mathrm{9xz}+\mathrm{27x} \\ $$

Commented by mahdipoor last updated on 14/Dec/22

±∞  get  x=y=z ⇒f=3x^3 −18x^2 +27x  min and max f=±∞

$$\pm\infty \\ $$$${get}\:\:{x}={y}={z}\:\Rightarrow{f}=\mathrm{3}{x}^{\mathrm{3}} −\mathrm{18}{x}^{\mathrm{2}} +\mathrm{27}{x} \\ $$$${min}\:{and}\:{max}\:{f}=\pm\infty \\ $$

Terms of Service

Privacy Policy

Contact: info@tinkutara.com