The following Cubic Eqn should have three roots - what are they?

x^3-27=0

RAM,

27 = 3^{3} so x^{3} - 27 is a difference of cubes. Factor x^{3} - 3^{3} as a difference of cubes. This will give you one root immediately. The other two can be found from the remaining factor using the general quadratic expression.

Penny

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