Question 48636: Please help. These problems look so easy but I just can't seem to get the right answer.
First Problem:
1/√3 + 4/√27 - 2/√12
Second Problem:
2 cubed root of 27x + 2 cubed root 64x
I came up with 2 answers:
14 cubed root of x -OR- 2 cubed root of 91x
Which one is correct??
Found 2 solutions by consc198, ikleyn:
Answer by consc198(59)   (Show Source):
You can put this solution on YOUR website! First Problem
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1/√3 + 4/√27 - 2/√12
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0.577 + 0.769 + 0.577 = 1.923
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Second problem
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2 cubed root of 27x + 2 cubed root 64x
I came up with 2 answers:
14 cubed root of x -OR- 2 cubed root of 91x
Which one is correct??
__________________________________________
The correct one is 2 cubed root of 91x
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Answers
Ist problem: 1.923
2nd problem: 2 cubed root of 91x
Answer by ikleyn(53937)  (Show Source):
You can put this solution on YOUR website! .
Please help. These problems look so easy but I just can't seem to get the right answer.
First Problem:
1/√3 + 4/√27 - 2/√12
Second Problem:
2 cubed root of 27x + 2 cubed root 64x
I came up with 2 answers:
14 cubed root of x -OR- 2 cubed root of 91x
Which one is correct??
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In the post by @consc198, first solution is irrelevant, while second solution is incorrect.
For right solutions, see what follows.
F i r s t p r o b l e m
It does not say what to do and what is required, but according to common sense,
they want you to simplify and to reduce to simple canonic final form.
 +  -  =
= +  -  =
=  = =  =  . ANSWER
S e c o n d p r o b l e m
 +  =
Notice that 27 = 3^3, while 64 = 4^3.
So, we continue the chain of equalities
=  =  +  =  . the correct ANSWER
Solved.
As this person, @consc198, solves simple standard Math problems, he deserves to be excluded
from everywhere of an educational community, because he is not able to teach in a right way.
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