k!(k + 1) = (k + 1)!

How does the left simplify to the expression on the right?

(I understand what factorial is, and I can find rules for multiplying two factorials, but I don't have any rules for multiplying a sum by a factorial.)

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k!(k + 1) = (k + 1)!

How does the left simplify to the expression on the right?

(I understand what factorial is, and I can find rules for multiplying two factorials, but I don't have any rules for multiplying a sum by a factorial.)

How does the left simplify to the expression on the right?

(I understand what factorial is, and I can find rules for multiplying two factorials, but I don't have any rules for multiplying a sum by a factorial.)

- syntaxerror
**Posts:**1**Joined:**Wed Jul 24, 2013 6:00 pm

syntaxerror wrote:k!(k + 1) = (k + 1)!

How does the left simplify to the expression on the right?

(I understand what factorial is, and I can find rules for multiplying two factorials, but I don't have any rules for multiplying a sum by a factorial.)

k!(k+1)=(k+1)*k!

=(k+1)*(k)(k-1)(k-2)...(3)(2)(1)

=(k+1)!

Look carefully that k=(k+1)-1

- jg.allinsymbols
**Posts:**71**Joined:**Sat Dec 29, 2012 2:42 am

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