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#1 2024-05-27 06:38:58
- mathxyz
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- From: Brooklyn, NY
- Registered: 2024-02-24
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Square Root Prove
Give an example to show that sqrt{a^2} is not equal to a. Use it to explain why sqrt{a^2} = | a |.
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#2 2024-05-27 08:14:43
- Bob
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- Registered: 2010-06-20
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Re: Square Root Prove
If a=-5 then a^2 =25. Sqr(number) is taken to mean the positive square root which would be 5 not -5.
By writing |a| this difficulty is avoided.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob 
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