A problem in Quadratic Equations

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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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