I am having trouble understanding the range in f(x,y)=4x^2+9y^2. The answer is z>=0 but my book is not helping me understand how to find this. Can someone please help explain this to me? Thank you.
I am having trouble understanding the range in f(x,y)=4x^2+9y^2. The answer is z>=0 but my book is not helping me understand how to find this. Can someone please help explain this to me? Thank you.
we have $\displaystyle z = 4x^2 + 9y^2$
now, $\displaystyle 4x^2 \ge 0$ for all $\displaystyle x$ and $\displaystyle 9y^2 \ge 0$ for all $\displaystyle y$. 0 is the minimum for both of these