Steve S. answered • 03/18/14

Tutor

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Tutoring in Precalculus, Trig, and Differential Calculus

"what is factoral?" [You missed the "i" in factorial.]

If n is a non-negative integer, then we can find its "factorial".

n factorial is written in math as "n!". I.e., we use the exclamation point to denote factorial.

3! = 3*2*1, where * means multiplication.

10! = 10*9*8*7*6*5*4*3*2*1

n! = n*(n-1)*(n-2)*...*2*1

AND 0! := 1, where “:=“ means “is defined as”.

On my calculator I have a key labelled "x!".

If I key in 20 and press x! I get 2.43290200817664*10^18.

If n is a non-negative integer, then we can find its "factorial".

n factorial is written in math as "n!". I.e., we use the exclamation point to denote factorial.

3! = 3*2*1, where * means multiplication.

10! = 10*9*8*7*6*5*4*3*2*1

n! = n*(n-1)*(n-2)*...*2*1

AND 0! := 1, where “:=“ means “is defined as”.

On my calculator I have a key labelled "x!".

If I key in 20 and press x! I get 2.43290200817664*10^18.

But if I key in 200 and press x! I get "Overflow" on my MacBook or "Error" on my iPhone.

What's the largest integer you can key in on your calculator and press "x!" without getting an error? [An error means you've exceeded the capacity of your calculator. In computerese you have an overflow error.]

You can also key in a non-negative real number and "x!" will give you a result. How does it do that? It uses a function of real numbers that equal n! for non-negative integers but that essentially draws a smooth curve between the graphed points of y = n!. See http://www.wyzant.com/resources/files/265570/x_factorial AND http://en.wikipedia.org/wiki/Factorial#Extension_of_factorial_to_non-integer_values_of_argument.

E.g.: (pi)! ≈ 7.188082728976031

What's the largest integer you can key in on your calculator and press "x!" without getting an error? [An error means you've exceeded the capacity of your calculator. In computerese you have an overflow error.]

You can also key in a non-negative real number and "x!" will give you a result. How does it do that? It uses a function of real numbers that equal n! for non-negative integers but that essentially draws a smooth curve between the graphed points of y = n!. See http://www.wyzant.com/resources/files/265570/x_factorial AND http://en.wikipedia.org/wiki/Factorial#Extension_of_factorial_to_non-integer_values_of_argument.

E.g.: (pi)! ≈ 7.188082728976031