Is $y= x^3$ a direct variation?

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Answer 1 · 2015-05-26T23:08:41

$y=x^3$ is not a direct variation

If it were a direct variation, doubling the value of $x$ (for example) would double the value of $y$ , but this is obviously not the case.

A direct variation must be expressible in the form
$y = c* x$ for some constant $c$

Is y= x^3y= x^3 a direct variation?