Problem I could not solved.

(n-3)(n-4)!/(n-5)(n-6)!=?

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`2 \times 3`	$2 \times 3$
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Comments

@Mehdi Balti, could you please clarify what the problem is? Thanks.

Victor Loh - 5 years, 11 months ago

It's factorial and the answer will be in positive integer.Not in decimal (n-3)(n-4)!/(n-5)(n-6)!=?

Mehdi Balti - 5 years, 11 months ago

Based on how you've clarified the problem, I'm assuming you wish to find the value of

$x = \frac{(n-4)!(n-3)}{(n-6)!(n-5)},$

where $x$ is a positive integer.

Note that

$\begin{aligned} x &= \frac{(n-4)!(n-3)}{(n-6)!(n-5)} \nonumber \\ &= \frac{(n-3)[(n-4)(n-5)(n-6)\cdots(3)(2)(1)]}{(n-5)[(n-6)(n-7)(n-8)\cdots(3)(2)(1)]} \nonumber \\ &= \frac{(n-3)(n-4)(n-5)!}{(n-5)!} \nonumber \\ &= (n-3)(n-4) \nonumber \end{aligned}$

This value is different for different values of $n$ . I'm not sure if this is what you want, although $(n-3)(n-4)$ is clearly a positive integer for positive integer values of $n$ . Please clarify further. Thanks!

Victor Loh - 5 years, 11 months ago

Yes n value is positive integer.Really thanks @Victor Loh I got it completely Now :) Thumps up for u Cheers :)

Mehdi Balti - 5 years, 11 months ago

If I would not given the value but say that it's positive integer then how would you solve this ?Answer should be in positive integer.

Mehdi Balti - 5 years, 11 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$