why I'm getting 2 answers contrary to each other

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kh ibrahim
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why I'm getting 2 answers contrary to each other

Unread post by kh ibrahim » Wed Oct 26, 2016 8:02 am

It is an extra of general math on chapter 6.3
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why I'm getting 2 answers contrary to each other
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kh ibrahim
Posts:17
Joined:Mon May 09, 2016 11:18 am

Re: why I'm getting 2 answers contrary to each other

Unread post by kh ibrahim » Wed Oct 26, 2016 9:53 pm

Perhaps, nobody is getting my question.In the attachment you can see I got two results but they are contrary.The theorem is sum of any two sides of a triangle is greater than twice of the median drawn to the third side.Firstly, I proved that.It was AB+AC>2AD.However, interesting thing was in the second part where I proved the opposite thing which was 2AD>AB+AC.How is it possible?Does this mean that this theorem is wrong?

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nahin munkar
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Re: why I'm getting 2 answers contrary to each other

Unread post by nahin munkar » Thu Oct 27, 2016 12:14 pm

kh ibrahim wrote:Perhaps, nobody is getting my question.In the attachment you can see I got two results but they are contrary.The theorem is sum of any two sides of a triangle is greater than twice of the median drawn to the third side.Firstly, I proved that.It was AB+AC>2AD.However, interesting thing was in the second part where I proved the opposite thing which was 2AD>AB+AC.How is it possible?Does this mean that this theorem is wrong?
Nope, the theorem is not wrong. :) It's your little misunderstanding of the inequality section. 8-)
# Mathematicians stand on each other's shoulders. ~ Carl Friedrich Gauss

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nahin munkar
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Re: why I'm getting 2 answers contrary to each other

Unread post by nahin munkar » Thu Oct 27, 2016 12:30 pm

kh ibrahim wrote:Perhaps, nobody is getting my question.In the attachment you can see I got two results but they are contrary.The theorem is sum of any two sides of a triangle is greater than twice of the median drawn to the third side.Firstly, I proved that.It was AB+AC>2AD.However, interesting thing was in the second part where I proved the opposite thing which was 2AD>AB+AC.How is it possible?Does this mean that this theorem is wrong?
Look, ur second result is not always true.
IF, $a$ > $b$, & $c$ > $d$ , then it is not always true that, $a-c$ > $b-d$ (that ur $2$nd result says.)
A counter-example can be stated, $(a,b,c,d)$= $(10,8,7,4)$. :) Hope this helps. :D
# Mathematicians stand on each other's shoulders. ~ Carl Friedrich Gauss

kh ibrahim
Posts:17
Joined:Mon May 09, 2016 11:18 am

Re: why I'm getting 2 answers contrary to each other

Unread post by kh ibrahim » Thu Oct 27, 2016 3:28 pm

You said that my second result is not always true.So if it is true in some cases, then wont the theorem be wrong?

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