A problem in Quadratic Equations

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Homework Help Overview

The discussion revolves around finding the number of solutions to the equation $$\sqrt {x^2}-\sqrt {(x-1)^2} + \sqrt {(x-2)^2}=\sqrt {5}$$, which involves understanding the properties of square roots and absolute values in the context of quadratic equations.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants express confusion about how to start solving the equation and question the meaning of square roots of squares. There is a discussion about the general form of $$\sqrt{a^2}$$ and its implications for the equation.

Discussion Status

Some participants have identified that the equation can be rewritten using absolute values, leading to a clearer path for solving it. Guidance has been provided regarding plotting the function to visualize the solutions.

Contextual Notes

Participants are working under the constraints of homework rules, which may limit the amount of direct assistance they can receive. There is an ongoing exploration of the assumptions related to the properties of square roots and absolute values.

Wrichik Basu
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Homework Statement



Find the number of solutions of the equation $$\sqrt {x^2}-\sqrt {(x-1)^2} + \sqrt {(x-2)^2}=\sqrt {5}$$
Answer given: 2

Homework Equations



The Attempt at a Solution



Completely clueless as to where to start.
 
Last edited:
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Wrichik Basu said:

Homework Statement



Find the number of solutions of the equation $$\sqrt {x^2}-\sqrt {(x-1)^2} + \sqrt {(x-2)^2}=\sqrt {5}$$
Answer given: 2

Homework Equations



The Attempt at a Solution



Completely clueless as to where to start.
What is the square root of the square of a number ? ##\sqrt{a^2} = ?##
 
Last edited:
Wrichik Basu said:

Homework Statement



Find the number of solutions of the equation $$\sqrt {x^2}-\sqrt {(x-1)^2} + \sqrt {(x-2)^2}=\sqrt {5}$$
Answer given: 2

.
Write the equation without square roots and squares. Do you know what is ##\sqrt{3^2}##? and ##\sqrt{(-3)^2}##? And what is ##\sqrt{a^2}## in general?
 
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ehild said:
Write the equation without square roots and squares. Do you know what is ##\sqrt{3^2}##? and ##\sqrt{(-3)^2}##? And what is ##\sqrt{a^2}## in general?
##\sqrt{a^2} = |a|##, that much I know. And the others are both 3.
 
ehild said:
Write the equation without square roots and squares. Do you know what is ##\sqrt{3^2}##? and ##\sqrt{(-3)^2}##? And what is ##\sqrt{a^2}## in general?
You mean to say that the expression reduces to ## |x|-|x-1|+|x-2|=\sqrt {5}##?

Then I can solve it without problem, just tell if my evaluation is correct.
 
Wrichik Basu said:
You mean to say that the expression reduces to ## |x|-|x-1|+|x-2|=\sqrt {5}##?

Then I can solve it without problem, just tell if my evaluation is correct.
Yes, it is correct. Just plot the function, and see, if it can take the value √5, and how many times.
 
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ehild said:
Yes, it is correct. Just plot the function, and see, if it can take the value √5, and how many times.
Right, plot on a number line and... I understood. Thank you, sir. :partytime:
 
Well, this is the plot

upload_2017-5-22_23-27-0.png
 
Last edited:

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