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 Question from Kenny, a parent: 3 over "x" plus 5. I don't know this is either a polynomial and if so how would you define it.

Hi Kenny,

I am not sure if you mean

$\frac{3}{x} + 5$

or

$\frac{3}{x + 5}$

but in either case this is not a polynomial.

An integer divided by a nonzero integer is called a rational number. In a similar way a polynomial divided by a polynomial is called a rational expression. Since both of the expressions above can be written as a polynomial divided by a polynomial I would call them rational expressions.

Harley

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