A+2b=2a+b=>1=2. please tell me what is the problem

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The discussion centers on a mathematical error in the manipulation of the equation a + 2b = 2a + b, which leads to the incorrect conclusion that 1 = 2. The mistake arises when dividing by a - b, which equals zero if a = b, thus making the division invalid. The thread emphasizes that the equality ax = bx only holds true if x is nonzero. The correct approach involves factoring out (a - b)x = 0, leading to the conclusion that either a = b or x = 0. This highlights the importance of not dividing by zero in algebraic manipulations.
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if we get:

a+2b=2a+b
=>a-b=2a-2b
=>a-b=2(a-b)
=>1=2

I can't figure out the problem in it..please tell me
 
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Does 2*0=3*0 also imply 2=3??
 
waqarrashid33 said:
if we get:

a+2b=2a+b
So 2b- b= 2a- a which gives a= b.

=>a-b=2a-2b
=>a-b=2(a-b)
=>1=2
Since a= b, a- b= 0 and you cannot divide by 0.0

I can't figure out the problem in it..please tell me
 
Note that the law

ax=bx~\Rightarrow~a=b

Only holds if x is nonzero!

The correct way in solving this is

ax=bx~\Rightarrow~ ax-bx=0~\Rightarrow~(a-b)x=0~\Rightarrow ~a-b=0~\text{or}~x=0
 
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