12 votes 12 votes A political party orders an arch for the entrance to the ground in which the annual convention is being held. The profile of the arch follows the equation $y=2x-0.1x^{2}$ where $y$ is the height of the arch in meters. The maximum possible height of the arch is $8$ meters $10$ meters $12$ meters $14$ meters Quantitative Aptitude gatecse-2012 quantitative-aptitude normal maxima-minima + – gatecse asked Sep 29, 2014 • edited Jun 7, 2018 by Milicevic3306 gatecse 3.1k views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
Best answer 14 votes 14 votes B. $10$ $y = 2x - 0.1x^{2}$ $\frac{\mathrm{d} y}{\mathrm{d} x} = 2 - 2\times 0.1x$ $ \frac{\mathrm{d} y}{\mathrm{d} x} =0 \implies x=10$ So, $y= 20-10=10$ shree answered Oct 24, 2014 • edited Jun 18, 2021 by Lakshman Bhaiya shree comment Share Follow See 1 comment See all 1 1 comment reply Prateek K commented Apr 20, 2018 reply Follow Share Why dy/dx is 0? 2 votes 2 votes Please log in or register to add a comment.
1 votes 1 votes y=2x - 0.1x^2 it's basically an equation of parabola (x-10)^2 = - 10(y-10) // it's form of x^2= -4ay graph will go downward :- Prateek kumar answered Jan 28, 2018 Prateek kumar comment Share Follow See all 0 reply Please log in or register to add a comment.