SOLUTION: simplify by factoring 5 square root 96x^12y^15

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Question 683835: simplify by factoring 5 square root 96x^12y^15
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
Only one kind of root is called a "SQUARE" root.  Sometimes students
get the wrong impression that all roots are called "SQUARE" roots, but
this is false.

simplify by factoring 5 square root 96x^12y^15

Did you mean this root%285%2C96x%5E12y%5E15%29?

If so that is NOT a "SQUARE" root but a FIFTH root.

If it were as you stated it would be 5%2Asqrt%2896x%5E12y%5E15%29

which is an entirely different problem.

If you meant the FIFTH root, not the SQUARE root, then you change
x%5E12 to x%5E10%2Ax%5E2 because 10 is the largest exponent
divisible by 5.  We also change 96 to 32%2A3 or 2%5E5%2A3.
We do not need to change y%5E15 because 15 is already divisible
by 5, the index of the 5th root.

root%285%2C96x%5E12y%5E15%29 = root%285%2C32%2A3%2Ax%5E10%2Ax%5E2%2Ay%5E15%29 =

root%285%2C2%5E5%2A3%2Ax%5E10%2Ax%5E2%2Ay%5E15%29 =
  
Now we divide each exponent that is divisible by 5 and bring it out
from under the radical with the exponent divided by the index 5:

3%5E1%2Ax%5E2%2Ay%5E3%2Aroot%285%2C3%2Ax%5E2%29 and you can drop the 1 exponent for x

3%2Ax%5E2%2Ay%5E3%2Aroot%285%2C3%2Ax%5E2%29

If you really meant "SQUARE ROOT", like this:

5%2Asqrt%2896x%5E12y%5E15%29

Then the index is understood to be 2.  I'll put the index:

root%282%2C96x%5E12y%5E15%29

then you do not need to change x%5E12 because 12 is already
divisible by 2.  We change 96 to 16%2A6 or 2%5E4%2A6, so
that the exponent 4 is divisible by 2.
We change y%5E15 to y%5E14%2Ay.

5%2Aroot%282%2C16%2A6%2Ax%5E12y%5E14%2Ay%29

5%2Aroot%282%2C2%5E4%2A6%2Ax%5E12y%5E14%2Ay%29

Now we divide each exponent by 2 that is divisible by 2 and bring it out
from under the radical with the exponent divided by the index 2:

5%2A2%5E2%2Ax%5E6%2Ay%5E7%2Aroot%282%2C6%2Ay%29 =

5%2A4%2Ax%5E6%2Ay%5E7%2Aroot%282%2C6%2Ay%29

and we drop the 2 index because it's understood when the root is a
SQUARE root and not some other root such as the FIFTH root.

5%2A4x%5E6y%5E7%2Asqrt%286y%29 =

20x%5E6y%5E7%2Asqrt%286y%29

Edwin