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Solve equation for real solution x^3-1=0
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you just add 1 to both sides
then you know the cube root of 1 is just 1
Posted by baracuda123 on December 12, 2011 at 3:53 AM (Answer #1)
You need to remember the formula of the difference of two perfect cubes:
`a^3-b^3 = (a-b)(a^2+ab+b^2)`
Comparing the difference of two cubes to the given equation yields:
`x^3-1 = (x-1)(x^2 + x + 1)`
You need to solve for x the product `(x-1)(x^2 + x + 1)` = 0.
x - 1 = 0 => x = 1
Notice that `x^2 + x + 1` > 0 `AA` x `in` R
The real solution to the given equation is x = 1.
Posted by sciencesolve on December 12, 2011 at 2:22 AM (Answer #2)
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