SOLUTION: If z = 2<sup>14</sup>&#8729;3<sup>20</sup>, what is the largest power of 12 that evenly divides into the square root of z?

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Question 1049891: If z = 214∙320, what is the largest
power of 12 that evenly divides into the square root of z?

Found 2 solutions by Alan3354, Edwin McCravy:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
z = 2^14*3^20
sqrt%28z%29+=+2%5E7%2A3%5E10
--> 2^7
==================
Captain Obvious is correct, my answer is not right.
I misread it, thought it said power of 2.
---
I wouldn't try to make a Master's thesis out of it, tho.

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
The solution above is incorrect!
If z = 214∙320, what is the largest 
power of 12 that evenly divides into the square root of z?

12%22%22=%22%222%5E2%2A3

Let p = the largest power of 12 that evenly divides into the
square root of z

12%5Ep%22%22=%22%22%282%5E2%2A3%29%5Ep

12%5Ep%22%22=%22%222%5E%282p%29%2A3%5Ep

We are given:

z%22%22=%22%222%5E14%2A3%5E20

We find the square root of z

sqrt%28z%29%22%22=%22%22sqrt%282%5E14%2A3%5E20%29

sqrt%28z%29%22%22=%22%222%5E7%2A3%5E10

Now we divide 12%5Ep INTO sqrt%28z%29, which amounts to
dividing sqrt%28z%29 BY 12%5Ep

sqrt%28z%29%2F%2812%5Ep%29%22%22=%22%22%282%5E7%2A3%5E10%29%2F%282%5E%282p%29%2A3%5Ep%29

Subtracting exponents on the right

sqrt%28z%29%2F%2812%5Ep%29%22%22=%22%22%282%5E%287-2p%29%2A3%5E%2810-p%29%29

Negative exponents cause denominators. Therefore both those 
exponents must be non-negative (greater than or equal to zero) 
in order for the above result to be an integer, so we have:

7-2p%22%22%3E=%22%220 and 10-p%22%22%3E=%22%220

-2p%22%22%3E=%22%22-7 and -p%22%22%3E=%22%22-10

Remember that the inequality reverses when dividing 
by a negative number:

p%22%22%3C=%22%22%28-7%29%2F%28-2%29 and p%22%22%3C=%22%22%28-10%29%2F%28-1%29

 p%22%22%3C=%22%227%2F2 and p%22%22%3C=%22%2210%29

p%22%22%3C=%22%223%261%2F2 and p%22%22%3C=%22%2210%29

The largest integer value of p that satisfies both those is p = 3.

Answer: The largest power of 12 that evenly divides into the square 
root of z is 3.

Edwin