Multiple roots what is that??

[Guest]

3x^2-12x+12=0

Does this equation have multiple roots? I have no idea. How can you tell?

The solution to this equation is x=2 and x=2

3(2)^2-12(2)+12=0
12-24+12=0

Correct?

 

[james cook]

i think the answers were x=2 & x=-2

both these will fit as -2^2 also equalls 4

 

[ting]

For ax^2 +bx + c.

If the discriminant

b^2 - 4ac = 0

Then the equation has one repeated root.

(-12)^2 - (4*3*12) = 0

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

3x^2-12x+12

factors to.

3(x - 2)^2

 

[Denis]

3x^2-12x+12=0
Does this equation have multiple roots? I have no idea. How can you tell?
The solution to this equation is x=2 and x=2
3(2)^2-12(2)+12=0
12-24+12=0
Correct?

x = 2 is ONLY solution; so NO multiple roots.

Divide each term of your equation by 3:
x^2 - 4x + 4 = 0
(x - 2)(x - 2) = 0
x = 2 or x = 2 : which is what you have

HOW did YOU get x=2 ?

 

[Guest]

That is what the instructor told us to use??

 

[stapel]

That is what the instructor told us to use??

Earlier, you said "x = 2" was "the solution". Now you're saying that "x = 2" is "what he told us to use". Is "x = 2" part of the problem or part of the solution?

I fear we are talking at cross-purposes. Please reply with the full and exact text of the exercise and its instructions. Thank you.

Eliz.

 

[Guest]

That is exactly how it reads.
He gave us some other choices for x, but they don't work.

x=1 and x=2
x=2 and x=2
x=2 and x=4
x=3 and x=1

I picked x=2 and x=2 because it worked.