Adding RadicalsDate: 9/11/96 at 22:33:11 From: Anonymous Subject: Adding Radicals I have absolutely no idea how to add radicals. I can multiply and divide fine, but I can't add. Problems witn obvious answers (root 81 + root 25) I can do, but problems not involving perfect squares I can't do. Date: 9/12/96 at 11:37:2 From: Doctor Beth Subject: Re: Adding Radicals One thing to remember when adding radicals is that only the ones that are alike can be added together. So for example, you can't do anything to simplify root(3) + root(5) because 3 and 5 are different numbers. The only time that you can add radicals together is if they have the same number under them: like 2*root(2) + 3*root(2) = 5*root(2). This works just the same way that you can add 2x +3x = 5x. Taking that a little further, if the radicals can be simplified in a way to make them have the same number inside them, then you can also add them. For example, if I wanted to simplify root(8) + root(32), I would first simplify root(8) as root(2*2*2) which equals 2*root(2). Then I'd also recognize that root(32)=root(4*4*2)=4*root(2). (Basically, when I try to simplify square roots, I look for perfect squares that are inside them.) Now I have root(8)+root(32) = 2*root(2)+4*root(2) = 6*root(2). I hope this helps! -Doctor Beth, The Math Forum Check out our web site! http://mathforum.org/dr.math/ |
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