Can factorial ever be 0? @blackpenredpen

Uploaded February 2026 | Updated September 2026, 1 week ago

We know that zero factorial is equal to 1, i.e. 0!=1, but can we solve the equation x factorial is equal to 0, i.e., x!=0? We will use the regular definition of n factorial, as well as the integration extension of the factorial to see if x!=0 is possible or not. Note that although the graph of y=x! does NOT cross the x-axis, we cannot say x!=0 because of that. Think about x^2+1=0 has complex solutions. So, is there any solution?
Check out can x^x=0? youtu.be/s4YHRtvOVB4?si=wiIPlvXtjEQOe1r5

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