Find the values of m for which the equation has 2 roots

Creating a new topic here requires registration. All other forums are without registration.

Find the values of m for which the equation has 2 roots

Postby Math Tutor » Wed Nov 02, 2011 1:00 pm

Find the values of m for which the equation has 2 different roots.
[tex](x - 1)(mx^2 - x + 2m - 1) = 0[/tex]
Math Tutor
Site Admin
 
Posts: 495
Joined: Sun Oct 09, 2005 11:37 am
Reputation: 92

Re: Find the values of m for which the equation has 2 roots

Postby Guest » Tue Nov 08, 2011 4:40 pm

It is analyzed the equation: mx^2-x+2m-1

1). f(x_0) = f`(x_0) = 0 => m = (1+/- sqrt(3))/4 => x_1 = 1, x_2 = +/-sqrt(3) - 1

2). Delta = 0 => m = (1+/- sqrt(3))/4 => x_1 = 1, x_2 = +/-sqrt(3) - 1


y0urshad0w
Guest
 

Re: Find the values of m for which the equation has 2 roots

Postby Math Tutor » Wed Nov 09, 2011 1:22 pm

I do not understand why do you do these calculations:

1). f(x_0) = f`(x_0) = 0 => m = (1+/- sqrt(3))/4 => x_1 = 1, x_2 = +/-sqrt(3) - 1

Math Tutor
Site Admin
 
Posts: 495
Joined: Sun Oct 09, 2005 11:37 am
Reputation: 92

Re: Find the values of m for which the equation has 2 roots

Postby Guest » Sat Nov 12, 2011 5:35 pm

[tex]m=\frac{1-\sqrt{3}}{4}[/tex] and [tex]m=\frac{1+\sqrt{3}}{4}[/tex]
its what i get ;]
Guest
 

Re: Find the values of m for which the equation has 2 roots

Postby Math Tutor » Sun Nov 13, 2011 8:59 am

Yes last answers are correct.
Let's explain the solution:
x-1= 0 -> the first root
so [tex]mx^2-x+2m-1 = 0[/tex] must have exactly one root so we have to find for which m the discriminant=0

Math Tutor
Site Admin
 
Posts: 495
Joined: Sun Oct 09, 2005 11:37 am
Reputation: 92

Re: Find the values of m for which the equation has 2 roots

Postby Guest » Tue Nov 15, 2011 1:44 pm

Mrs. Teacher, you must master mathematics in order to understand it. There are still some awesome ways to
work it out. YS
Guest
 


Return to Math Problem of the Week



Who is online

Users browsing this forum: No registered users and 1 guest