Calculus Q: Stumped on Problem Statement & Equations

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Homework Help Overview

The original poster attempts to review a calculus problem involving expressions with square roots and a fraction. The problem statement is unclear, and there is uncertainty about the nature of the question being posed.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • Participants question the clarity of the problem statement and whether the expressions provided are meant to be simplified or equated. Some suggest using the conjugate to simplify the expression, while others express doubt about the correctness of the problem as presented.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the problem. Some guidance has been offered regarding simplification techniques, but there is no consensus on the nature of the original question or its validity.

Contextual Notes

There is a noted lack of information in the problem statement, leading to confusion about what is being asked. The original poster expresses frustration and has considered moving on to other problems.

physics=death
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Homework Statement



So, I'm trying to review on calculus since I haven't done any in a year and I was skimming the web for problems and I found this. It's got me stumped.

Question:
x
---------------------
[sqrt(x-1)-sqrt(x)]

Solution:
[(2-sqrt(2-x))*(sqrt(x)+sqrt(2-x))]
---------------------------------------
2x-2

That was all that was given. I don't even know how to start this. Anything that would help get me started would be appreciated. :)

Homework Equations


Above

The Attempt at a Solution


Well, at first I tried multiplying both sides with sqrt(x-1)+sqrt(x) then simplifying it to see if it matches the solution. But nothing. I'm wondering if the question wants me to find the derivative, integral, I really don't know.
 
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so what's the question? that just look like a few equations to me...

however (try clicking on tex below to see how its written) if you have
[tex]\frac{x}{\sqrt{x-1} -\sqrt{x}}[/tex]

and want to simplify the usual way is to multiply by the "conjugate" this will remove any root terms from the denominator
[tex]\frac{x}{\sqrt{x-1} -\sqrt{x}} = \frac{x}{\sqrt{x-1} -\sqrt{x}} <br /> \frac{\sqrt{x-1} + \sqrt{x}}{\sqrt{x-1} + \sqrt{x}}[/tex]

so try multiplying out and see where you end up
 
Yeah, what's the question? lanedance's suggestion would ordinarily be good advice, but in this case the two expressions (they are not equations) are not equal, so it's not a matter of simplifying, expanding, or manipulating one expression to get the other.

Are you sure you copied the problem correctly? If so, and what you show is all that is given, I would be inclined to not waste any more effort on this problem, and would look elsewhere for problems to do.
 
lanedance said:
so what's the question? that just look like a few equations to me...

however (try clicking on tex below to see how its written) if you have
[tex]\frac{x}{\sqrt{x-1} -\sqrt{x}}[/tex]

and want to simplify the usual way is to multiply by the "conjugate" this will remove any root terms from the denominator
[tex]\frac{x}{\sqrt{x-1} -\sqrt{x}} = \frac{x}{\sqrt{x-1} -\sqrt{x}} <br /> \frac{\sqrt{x-1} + \sqrt{x}}{\sqrt{x-1} + \sqrt{x}}[/tex]

so try multiplying out and see where you end up

Yes, that was my first try but it did not match the solution after simplifying. It's okay, I have already moved on to other problems and have been doing fine.

Mark44 said:
Yeah, what's the question? lanedance's suggestion would ordinarily be good advice, but in this case the two expressions (they are not equations) are not equal, so it's not a matter of simplifying, expanding, or manipulating one expression to get the other.

Are you sure you copied the problem correctly? If so, and what you show is all that is given, I would be inclined to not waste any more effort on this problem, and would look elsewhere for problems to do.

Those are the only pieces of information given which I agree is a bit shallow in terms of explaining the problem. Anyways, you're right. I have practiced other problems with no other difficulty.

==============

Since the question posted really does not state what the problem is, I cannot really tell what or how to solve.

I apologize if I wasted anyone's time, I have OCD when I cannot figure something out. >_<

Please lock this topic!
 
no worries, people just want to help, so the clearer the better - good you're getting into it
 

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