Question 1188657
.
<pre>

Let one number be 20+x.  Then the other number is 20-x,

and their product is (20+x)*(20-x) = 400 - 4x^2.


Looking at this quadratic form, it is obvious that the maximum is at x = 0;

so the numbers are  20  and 20.


<U>ANSWER</U>.  The product of such numbers is maximum when the numbers are equal, x= 20 and y= 20.
</pre>

Solved.


==============


In the future, do not pack more than one problem per post.


It is PROHIBITED by the rules of this forum.