Exercise 1.16 [bomc]

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sm.joty
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Re: Exercise 1.16 [bomc]

Unread post by sm.joty » Thu Oct 27, 2011 11:35 am

that means if b-2a is positive then we can square both sides.
Isn't it? :?:
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sourav das
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Re: Exercise 1.16 [bomc]

Unread post by sourav das » Thu Oct 27, 2011 12:07 pm

No, if $b-2a(\leq or \geq) m$ for some $m$ and you want to square then you have to make sure both $m$ and $b-2a$ are positive .
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*Mahi*
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Re: Exercise 1.16 [bomc]

Unread post by *Mahi* » Thu Oct 27, 2011 9:39 pm

General rule:
Squaring both sides of $a>b$ will be valid if and only if $|a|>|b|$ is true. And this can be true for the positive numbers $a,b$ only.
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