SOLUTION: how to solve= 1/cube root 4+ cube root 2 +1
i know the ans is cube root 2 -1 but i dont know how to solve it
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-> SOLUTION: how to solve= 1/cube root 4+ cube root 2 +1
i know the ans is cube root 2 -1 but i dont know how to solve it
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You can put this solution on YOUR website! First of all, please put multiple-term numerators and denominators in parentheses. What you posted meant:
But I'm quite sure you meant:
which should be posted as:
1/(cube root 4+ cube root 2 +1)
Tutors are more likely to respond if problems are posted clearly.
Clearing cube roots from a multiple-term denominator involves use of one or both of the following patterns:
A relatively fast way to simplify this requires that we recognizing that . Substituting this into our expression we get:
Now we need to recognize that this denominator matches the pattern of the second factor of with an "a" of and a "b" of 1. The pattern shows us that if we multiply that factor by (a-b) then we get . With all terms being perfect cubes, this will eliminate the cube roots.
So we multiply the numerator and denominator by (a-b) with an "a" of and a "b" of 1:
In the denominator, the pattern tells us what we get. In the numerator we just use the Distributive Property:
Simplifying...
(