Find the volume of solid bounded by the $x^2+y^2=a^2$ , $y^2 + z^2 =a^2$ , $x^2 + z^2 = a^2$
I can see that shadow in $x$y region is given by $x^2 + y^2 =a^2$ . but when I draw ray from shadow to up to both of cylinders hot do I know which cylinder it vl hit ie the $yz$ plane or $xz$ plane cylinder .