It would be easy if it is factors of x²-2x-3.
The problem was find 3x²-6x-1=0 using COMPLETING THE SQUARE (Quadratic)
Therefore the process of completing is:
(3x²-6x+9=10)/3
x²-2x+3=10/3
Now I am stuck at this equation, help please?
Update:It cannot be (x-1)(x+3) since it will be x²-2x-3
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Verified answer
3x²-6x-1= 0
3x²-6x-1= m² - 2mn + n²
m² = 3x² => m = V3x
2mn = 6x => 2V3xn = 6x => n = 3/V3
So:
(V3x - 3/V3)² = 3x² - 6x + 3
(V3x - 3/V3)² - 4 = 3x² - 6x + 3 - 4
(V3x - 3/V3)² - 4 = 3x² - 6x -1
(V3x - 3/V3)² - 4 = 0
(V3x - 3/V3)² = 4
V3x - 3/V3 = -2 or V3x - 3/V3 = 2
Let x' and x" the roots . So:
V3x' - 3/V3 = -2
V3x' = -2 + 3/V3
V3x' = (-2V3 + 3)/V3
x' = -2/V3 + 1
V3x" - 3/V3 = 2
V3x" = 2 + 3/V3
x" = 2/V3 + 1
3x²-6x-1 = a(x-x')(x-x")
3x²-6x-1 = 3(x- (-2/V3 + 1))(x-(2/V3 + 1)) (answer 1)
3x²-6x-1 = 3(x + 2/V3 - 1)(x- 2/V3 - 1)
3x²-6x-1 = 3( (x -1)+ 2/V3) ((x- 1) - 2/V3)
3x²-6x-1 = 3[(x -1)² - (2/V3)²]
3x²-6x-1 = 3[(x -1)² - (4/3)]
3x²-6x-1 = 3(x -1)² - 4 (answer 2)
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About the
x²-2x+3; a=1, b = -2, c = 3
Note that x²-2x+3 haven´t real roots:
delta = b² - 4ac = 4 - 4*1*3 = 4 - 12 = -8
Let x' and x" be the roots of x²-2x+3
x' = (-b-Vdelta)/2a = (2-2V2i)/2 = 2(1-V2i)/2 = (1-V2i)
x" = (-b+Vdelta)/2a = (2+2V2i)/2 = 2(1+V2i)/2 = (1+V2i)
x²-2x+3 = (x-x')(x-x")
x²-2x+3 = (x-(1-V2i))(x-(1+V2i)) (answer 1)
x²-2x+3 = (x-1+V2i)(x-1-V2i)
x²-2x+3 = ((x-1)+V2i)((x-1)-V2i)
x²-2x+3 = (x-1)² - (V2i)²
x²-2x+3 = (x-1)² - (2i²)
x²-2x+3 = (x-1)² - (2*-1)
x²-2x+3 = (x-1)² + 2 (answer 2)
x²-2x+3 = (x²-2x+1) + 2
Kisses from Brazil
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Firstly, you didn't divide the equation by 3 correctly. But are you sure you're supposed to divide the equation? Maybe you're supposed to complete the square using the original equation.
3x² - 6x - 1 = 0
3x² - 6x = 1
3(x² - 2x) = 1
Completing the square:
The coefficient of the x term is -2.
Half of -2 is -1.
Square the -1 and add to the polynomial:
3(x²-2x + (-1)²)
To keep the equation balanced you have to add THREE TIMES (-1)² to the right side.
3(x²-2x + (-1)²) = 1 + 3(-1)²
3(x-1)² = 4
(x-1)² = 4/3
x-1 = 屉(4/3)
= ±2/â3
x = 1 ± 2/â3
= 1 ± (2â3)/3
3x²-6x-1=0
3x²-6x-1+4=0+4
3x²-6x+3=4
3(x²-2x+1)=4
(x²-2x+1)=4/3
(x-1)²=4/3
(x-1) = 屉(4/3)
x=1+â(4/3) and
x= 1-â(4/3)
i'm assuming dat u want us to solve for x--rite??
Therefore the process of completing is:
(3x²-6x+9=10)/3
well u r a bit off here:
it is
3x²-6x+3=4
now
(x-1)² = 4/3
so x= 1 + 2/rt(3) and 1 - 2/rt(3)
here rt--> square root!
3x²-6x-1=0
3x^2-6x=1
divinding by 3
x^2-2x=1/3
x^2-2x+1=1/3+1
(x-1)^2=4/3
x-1=+-root(4/3)
x=((2 sqrt(3))/(3))+1
x=-((2 sqrt(3))/(3))+1
FACTORS ARE (X+1)(X-3)
y r u using completing the square method...??
use another..simpler than this...!