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#1 2008-12-01 12:50:39
- tobi's a good boy
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i forgot something
i forgot how to do square root
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#2 2008-12-01 13:26:45
- mathsyperson
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Re: i forgot something
Think of it as the opposite of squaring.
2 squared is 4, so the square root of 4 is 2.
etc.
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It wanted to be normal.
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#3 2008-12-01 16:45:01
- Jai Ganesh
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Re: i forgot something
Prime factorization is one of the easiest and best methods.
eg: Finding the square root of 324.
324=162x2 = 81 x 2 x 2 = 27 x 3 x 2 x 2 = 9 x 3 x 3 x 2 x 2 = 3 x 3 x 3 x 3 x 2 x 2
For every two same prime factors of the original number, take one of them for the square root.
Thus, √324 =3 x 3 x 2 = 18
Remember, the square root of a number x² is always ±x.
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#4 2008-12-02 01:11:01
- mathsyperson
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Re: i forgot something
That's something that not everyone agrees on.
The solutions of x² - k² = 0 are definitely x = ± k, but √(k²) is generally taken to be just k.
Why did the vector cross the road?
It wanted to be normal.
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#5 2009-01-20 10:07:18
- lightning
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Re: i forgot something
i don't know either so this is really helpful, so as an example -
the square root of 4 is 2?
because 2x2=4 and it all has to do with the table, am i right?
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#6 2009-01-20 10:13:55
- luca-deltodesco
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Re: i forgot something
That's something that not everyone agrees on.
The solutions of x² - k² = 0 are definitely x = ± k, but √(k²) is generally taken to be just k.
Does the symbol √ not refer specificaly to the 'principal' square root, aka the positive root, wherein simply 'square root' gives no such specifics, aka (x[sup]2[/sup])[sup]0.5[/sup] = ±x = ±√(x[sup]2[/sup])
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