Question 1071414
.
<pre>
{{{2*(1/2)*((pi*a^2)/4)}}} + {{{2*(1/2)*((pi*b^2)/4)}}} - {{{pi*(a^2+b^2)/4}}} = 0.
</pre>

In the left side the first two addends are the areas of the four semi-circles built on the sides of the rectangle.


The subtrahend is the area if the big circle.



Similar to that as

<pre>
     "the area of the square built on the hypotenuse of the right-angled triangle is equal to the sum of areas 
     of two squares built on its legs"
</pre>

(Pythagoras),


<pre>
     "the area of the semi-circle built on the hypotenuse of the right-angled triangle is equal to the sum of areas 
      of two semi-circles built on its legs"
</pre>

<U>Answer</U>.  0. Zero.  ZERO.