Rules of order - advanced situations?

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Rules of order - advanced situations?

by jzw » Thu Feb 16, 2012 2:32 pm
Obviously I know PEMDAS. But, what happens when ive got fractions and square roots in there too? In what order do I do the operation? For example:

y + the square root of x^2 + y^2
above is the numerator

OVER

z (the denominator)

z=2, y=3, x=4
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by rijul007 » Thu Feb 16, 2012 5:49 pm
jzw wrote:Obviously I know PEMDAS. But, what happens when ive got fractions and square roots in there too? In what order do I do the operation? For example:

y + the square root of x^2 + y^2
above is the numerator

OVER

z (the denominator)

z=2, y=3, x=4
hmmm.. :/

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by jzw » Thu Feb 16, 2012 8:29 pm
hi rijul007 - not sure if u meant to post an answer here...

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by tpr-becky » Sat Feb 18, 2012 11:20 am
you have to do the numbers inside the square root before you can take the square root so x^2 + y^2 = 25

then you do square roots before addition so 3 + 5 is on the numerator (only the positive root becuase of the sqrt sign). You can't do the fraction first because there is addtion in the numerator so you either have to resolve the addition or split the fraction first.

8/2 = 4
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