A problem in Quadratic Equations

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The equation $$\sqrt{x^2} - \sqrt{(x-1)^2} + \sqrt{(x-2)^2} = \sqrt{5}$$ simplifies to $$|x| - |x-1| + |x-2| = \sqrt{5}$$. The discussion emphasizes understanding the properties of square roots and absolute values. Participants suggest plotting the function to determine how many solutions exist. The conclusion reached is that there are two solutions to the equation. The problem-solving approach involves both algebraic manipulation and graphical analysis.
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.
 
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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} = ?##
 
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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

.
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
 
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