Submitted by Anonymous (not verified) on
Forums:
I'm up to the part where it says hence find the furthest distance from $O$. I have sketched a graph of $Y$ on $x$ which is a quadratic intersecting the x-axis at $ +- u^2/g $, but I can't seem to find its relevance to finding the maximum distance from $O$. Any help would be great please.
The distance from the origin
Submitted by stcs on
The distance from the origin squared is $x^2+y^2$, so for any given $x$ the greatest distance squared is $x^2+Y^2$. You just need to max this as a function of $x$. Your sketch may help a bit, but it is a calculus (or completing-the-square) problem now.