Imagine a cube with three circular holes cut from one face to another, when the width of the circles are the same width of the cube. If the width of the cube is 'x', what (with respect to x) is the volume left?

Is it anything like the answer to my formula:

e=(x sqrt2 - x)/(2 sqrt2)
f=x/(2 sqrt2)

Volume = 8(e^3 + (50316387 f e^2)/90474462)