How do you factor the expression #3x^3-27x#?

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Answer 1 · 2018-03-19T19:20:00

See a solution process below:

First, we can rewrite and factor as #x3# out of this expression as:

#(3x * x^2) - (3x * 9) =>#

#3x(x^2 - 9)#

Now we can use this formula for the special case of this quadratic to complete the factoring:

#color(red)(x)^2 - color(blue)(y)^2 = (color(red)(x) + color(blue)(y))(color(red)(x) - color(blue)(y))#

#3x(x^2 - 9) =>#

#3x(color(red)(x)^2 - color(blue)(3)^2) =>#

#3x(color(red)(x) + color(blue)(3))(color(red)(x) - color(blue)(3))#