What's the Square Root of 75?Date: 08/18/2002 at 00:03:18 From: Priss Edwards Subject: Sqrt 75 It's been years since I've been in college and my daughter needs help. Is the sqrt 75 15* sqrt 5 or 5* sqrt 15, or what? And why? Thanks for your help. Priss P.S. I've bookmarked this site for my daughter. Date: 08/18/2002 at 01:14:48 From: Doctor Paul Subject: Re: Sqrt 75 Write 75 as a product of primes: 75 = 3*5*5 So sqrt(75) = sqrt(3*5*5) Whenever you have two of the same number inside the square root, you can bring one of them outside and remove the other. Thus sqrt(75) = 5*sqrt(3). Another example: sqrt(6048) = sqrt(2*2*2*2*2*3*3*3*7) = 2*2*3*sqrt(2*3*7) = 12*sqrt(42) I hope this helps. Please write back if you'd like to talk about this some more. - Doctor Paul, The Math Forum http://mathforum.org/dr.math/ |
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