Is Algebraic Equality True? $\frac{x+y}{(x^2+y^2)} = \frac{1}{x+y}$

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The equation \(\frac{x+y}{(x^2+y^2)} = \frac{1}{x+y}\) is not algebraically correct. A specific example shows that \(\frac{2 + 3}{2^2 + 3^2} = \frac{5}{13}\) does not equal \(\frac{1}{5}\). The confusion arises from the misconception that \((x+y)^2\) equals \(x^2+y^2\), which is false. This misunderstanding is commonly referred to as the "freshman's dream." Therefore, the original equation is incorrect.
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Is \frac{x+y}{(x^2+y^2)} = \frac{1}{x+y}

would that be algebraically correct?
 
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whatlifeforme said:
Is \frac{x+y}{(x^2+y^2)} = \frac{1}{x+y}

would that be algebraically correct?

No, it is not.
 
whatlifeforme,
Would this be correct?

$$ \frac{2 + 3}{2^2 + 3^2} = \frac{1}{2 + 3}$$

More simply, this is asking whether 5/13 is equal to 1/5.
 
And I want to add that your mistake is the so-called "freshman's dream", that is, the incorrect idea that ##(x+y)^2=(x^2+y^2)##, which it does not.
 
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