MHB How to Strike Through Text in LaTeX?

AI Thread Summary
To strike through text in LaTeX, the \cancel{} command can be used, which is found in the algebra section of the Quick LaTeX tool. The discussion also includes a mathematical simplification of the factorial expression, showing that \(\frac{(a+1)!}{(a-2)!}\) simplifies to \(a(a+1)(a-1)\). The participants emphasize clarity in notation when presenting mathematical expressions. The conversation highlights the importance of using appropriate tools for formatting in LaTeX. Overall, the thread provides insights into both mathematical simplification and text formatting in LaTeX.
karush
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Simplify. Assume that $n$ and $m$ are positive integers,
$a>b$, and $a>2$.$\frac{\left(a+1\right)!}{\left(a-2\right)!}$

was helping a friend with this but was clueless
I know that n! $=n(n-1)(n-2) ... $
 
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We have that $$(a+1)!=(a+1)\cdot a\cdot (a-1)\cdot (a-2)\cdots 1=(a+1)\cdot a\cdot (a-1)\cdot (a-2)!$$
 
So finally
$$\frac{\left(a+1\right)!}{\left(a-2\right)!}=\frac{\left(a+1\right)a\left(a-1\right)\left(a-2\right)...}{\left(a-2\right)!}=\left(a+1\right)a\left(a-1\right)$$
 
karush said:
So finally
$$\frac{\left(a+1\right)!}{\left(a-2\right)!}=\frac{\left(a+1\right)a\left(a-1\right)\left(a-2\right)...}{\left(a-2\right)!}=\left(a+1\right)a\left(a-1\right)$$

While that is certainly correct, I think a more clear notation would be:

$$\frac{(a+1)!}{(a-2)!}=\frac{(a+1)a(a-1)\cancel{(a-2)!}}{\cancel{(a-2)!}}=a(a+1)(a-1)$$
 
how is a strike though done with latex didn't see a tool for that on the menu?
 
karush said:
how is a strike though done with latex didn't see a tool for that on the menu?

I used the \cancel{} command in my post...you can find 2 types of strikethrough in the "algebra" section of the "Quick $\LaTeX$ tool at the bottom right. :)
 
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