document.write( "Question 957853: how to solve= 1/cube root 4+ cube root 2 +1\r
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\n" ); document.write( "\n" ); document.write( "i know the ans is cube root 2 -1 but i dont know how to solve it
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Algebra.Com's Answer #585378 by jsmallt9(3758)\"\" \"About 
You can put this solution on YOUR website!
First of all, please put multiple-term numerators and denominators in parentheses. What you posted meant:
\n" ); document.write( "\"1%2Froot%283%2C+4%29+%2B+root%283%2C+2%29+%2B+1\"
\n" ); document.write( "But I'm quite sure you meant:
\n" ); document.write( "\"1%2F%28root%283%2C+4%29+%2B+root%283%2C+2%29+%2B+1%29\"
\n" ); document.write( "which should be posted as:
\n" ); document.write( "1/(cube root 4+ cube root 2 +1)
\n" ); document.write( "Tutors are more likely to respond if problems are posted clearly.

\n" ); document.write( "Clearing cube roots from a multiple-term denominator involves use of one or both of the following patterns:
  • \"a%5E3%2Bb%5E3+=+%28a%2Bb%29%28a%5E2-ab%2Bb%5E2%29\"
  • \"a%5E3-b%5E3+=+%28a-b%29%28a%5E2%2Bab%2Bb%5E2%29\"
A relatively fast way to simplify this requires that we recognizing that \"root%283%2C+4%29+=+%28root%283%2C+2%29%29%5E2\". Substituting this into our expression we get:
\n" ); document.write( "\"1%2F%28%28root%283%2C+2%29%29%5E2+%2B+root%283%2C+2%29+%2B+1%29\"
\n" ); document.write( "Now we need to recognize that this denominator matches the pattern of the second factor of \"a%5E3-b%5E3+=+%28a-b%29%28a%5E2%2Bab%2Bb%5E2%29\" with an \"a\" of \"root%283%2C+2%29\" and a \"b\" of 1. The pattern shows us that if we multiply that factor by (a-b) then we get \"a%5E3-b%5E3\". With all terms being perfect cubes, this will eliminate the cube roots.

\n" ); document.write( "So we multiply the numerator and denominator by (a-b) with an \"a\" of \"root%283%2C+2%29\" and a \"b\" of 1:
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\n" ); document.write( "In the denominator, the pattern tells us what we get. In the numerator we just use the Distributive Property:
\n" ); document.write( "\"%28root%283%2C+2%29+-+1%29%2F%28%28root%283%2C+2%29%29%5E3+-+%281%29%5E3%29%29\"
\n" ); document.write( "Simplifying...
\n" ); document.write( "\"%28root%283%2C+2%29+-+1%29%2F%282-1%29\"
\n" ); document.write( "\"%28root%283%2C+2%29+-+1%29%2F1\"
\n" ); document.write( "\"root%283%2C+2%29+-+1\"
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