Conceptual question on equations of the form ##x=ay^2+by+c##

AI Thread Summary
Quadratic equations typically take the form y=ax^2+bx+c, but they can also be expressed with switched variables, such as x=y^2+2y+1. In this case, x is considered a function of y, while y does not qualify as a function of x due to the presence of multiple values for y corresponding to a single x. For a relation to be a function, each input must yield a unique output, which is not satisfied here. Therefore, while x can be treated as dependent on y, the reverse does not hold true. This distinction is crucial in understanding the nature of the relationship between the variables.
chwala
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Homework Statement
This is my own question;
Relevant Equations
quadratic equations
Now i just need some clarification; we know that quadratic equations are equations of the form ##y=ax^2+bx+c## with ##a,b## and ##c## being constants and ##x## and ##y## variables.

Now my question is... can we also view/look at ##x=y^2+2y+1## as quadratic equations having switched the variables ? thanks...
 
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chwala said:
Homework Statement: This is my own question;
Relevant Equations: quadratic equations

Now i just need some clarification; we know that quadratic equations are equations of the form ##y=ax^2+bx+c## with ##a,b## and ##c## being constants and ##x## and ##y## variables.

Now my question is... can we also view/look at ##x=y^2+2y+1## as quadratic equations having switched the variables ? thanks...
Yes. Of course we can.

However, I hope you realize that in this case, ##x## is a function of ##y##, but ##y## is not a function of ##x##.
 
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SammyS said:
Yes. Of course we can.

However, I hope you realize that in this case, ##x## is a function of ##y##, but ##y## is not a function of ##x##.
yes @SammyS ...we now have ##x## as the dependent variable......but is the relation going to be a Function? as we require to obtain one unique value( one and only one) for ##y## for any value of ##xε\mathbb{R}##.
 
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it is a function of variable ##y##
 
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chwala said:
yes @SammyS ...we now have ##x## as the dependent variable......but is the relation going to be a Function? as we require to obtain one unique value( one and only one) for ##y## for any value of ##xε\mathbb{R}##.
I believe that I answered this in Post #2 .
 
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chwala said:
as we require to obtain one unique value( one and only one) for ##y## for any value of ##xε\mathbb{R}##.
But this is needed when ##y## is a function of ##x##.
If we have ##x=y^2## we can say that ##x## is a function of ##y##. But ##y## is not a function of ##x## because: ##y=\pm x^\frac {1}{2}##.
 
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