Proving two statements are the same (with words).

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SUMMARY

The discussion centers on the mathematical equivalence of the expressions ##(\sqrt{x})^2## and ##\sqrt{x^2}##. It is established that while both expressions yield the same result for nonnegative values of x, they differ in their domains. Specifically, ##\sqrt{x}## is defined only for nonnegative x, whereas ##\sqrt{x^2}## is defined for all real numbers. Therefore, the two expressions are equal only within their respective domains.

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angela107
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Homework Statement
Are ##(\sqrt{x})^2## and ##\sqrt{x^2}## always equal for all real numbers x?
Relevant Equations
n/a
As the question asks, I believe this statement is true. At least, technically. It is important to consider the domain of the function. Yes, ##sqrt(x)^2 = x##, but ##sqrt(x)## is only defined for nonnegative ##x##, whereas ##sqrt(x^2)## is defined for all ##x##, since ##x^2## is always nonnegative. The two functions are actually equal where they are both defined.

My question is, have my justified my solution well enough for a reader to understand what I'm saying?
 
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angela107 said:
Homework Statement:: Are ##(\sqrt{x})^2## and ##\sqrt{x^2}## always equal for all real numbers x?
Relevant Equations:: n/a

As the question asks, I believe this statement is true. At least, technically. It is important to consider the domain of the function. Yes, ##sqrt(x)^2 = x##, but ##sqrt(x)## is only defined for nonnegative ##x##, whereas ##sqrt(x^2)## is defined for all ##x##, since ##x^2## is always nonnegative. The two functions are actually equal where they are both defined.

My question is, have my justified my solution well enough for a reader to understand what I'm saying?
First off, those are expressions, not statements.
The question asks whether ##(\sqrt{x})^2## and ##\sqrt{x^2}## are always equal for all real numbers x.
Are the two expressions equal for, say, x = 1?

Keep in mind that where both expressions are defined is not necessarily all real numbers.
 

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