Solving for x: Are F(x) and G(x) Equivalent?

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F(x) simplifies to x when the denominator is not zero, but it is undefined at x=1 due to division by zero. G(x) is defined for all real numbers, including x=1. The equivalence of F(x) and G(x) depends on their domains; without explicit domain definitions, their equivalence cannot be confirmed. If the problem does not specify domains, it is assumed that F's domain excludes x=1 while G's includes it. Therefore, F(x) and G(x) are not equivalent due to differing domains.
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F(x) = (x^2 - x)/(x-1)
G(x)= x

I factored x^2-x and canceled denominator of f(x) which simplify to x

So it does equal x does not now matter that in original equation x cannot = 1 otherwise denominator = 0

I'm just making sure they are = and but maybe not equivalent. Trying to learn more of maths. Thank you.
 
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Is F(x) defined when x=1? Is G(x) defined there?

ehild
 
The problem doesn't say
 
Can you divide by zero? ehild
 
No but you can manipulate the equation to be x.
 
You manipulated it by dividing with an expression that can be zero. It is forbidden.
Try to input (1^2-1)/(1-1) in your calculator . What does it say? :-p


ehild
 
Do F and G have the same domains?
 
brycenrg said:
The problem doesn't say

If it doesn't state the domains then, strictly speaking, it is impossible to say whether the functions are equal. I can claim the functions f = x and g = 2x are equal if the domain is {0}. Conversely, f = x and g = x are different functions if I specify different domains.

If no value is specified for F(1), is 1 in F's domain?
Consider whether 1 might be in G's domain, and the consequences.
 
brycenrg said:
The problem doesn't say
It might be that the domains are implied - that is, the domain for each function might be the real numbers for which each function is defined. It might be that this is actually stated in the problem and you didn't include it in the problem description.

If there actually isn't any information given in the problem, what would be the implied domains for F and G?
 
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