SOLUTION: Simplify. Assume variables represent positive numbers 3 times the cubed root of 32 minus 7 times the cubed root of 108 Thank you very much i have been trying to solve this for

Algebra ->  Square-cubic-other-roots -> SOLUTION: Simplify. Assume variables represent positive numbers 3 times the cubed root of 32 minus 7 times the cubed root of 108 Thank you very much i have been trying to solve this for       Log On


   

Question 357281: Simplify. Assume variables represent positive numbers
3 times the cubed root of 32 minus 7 times the cubed root of 108
Thank you very much i have been trying to solve this for 2 days. I have factored 32 and 108 and taken the cubed roots. I cannot come up with the book answer of
-17 times the cubed root of 4
Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
32 = 4 * 8 = 4 * (2^3)

108 = 4 * 27 = 4 * (3^3)

3[cbrt(32)] = 3 * 2[cbrt(4)] = 6 cbrt(4)

7[cbrt(108)] = 7 * 3[cbrt(4)] = 21 cbrt(4)

subtracting gives ___ -15 cbrt(4)


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