Respuesta :
ANSWER
[tex]x=\frac{2-\sqrt{10}} {3}[/tex]
or
[tex]x=\frac{\sqrt{10}+2} {3}[/tex]
We have
[tex]3x^2-4x-2=0[/tex]
Since we cannot factor easily, we complete the square.
Adding 2 to both sides give,
[tex]3x^2-4x=2[/tex]
Dividing through by 3 gives
[tex]x^2-\frac{4}{3}x= \frac{2}{3}[/tex]
Adding [tex](-\frac{2}{3})^2[/tex] to both sides gives
[tex]x^2-\frac{4}{3}x+(-\frac{2}{3})^2= \frac{2}{3}+(-\frac{2}{3})^2[/tex]
The expression on the Left Hand side is a perfect square.
[tex](x-\frac{2}{3})^2= \frac{2}{3}+\frac{4}{9}[/tex]
[tex]\Rightarrow (x-\frac{2}{3})^2= \frac{10}{9}[/tex]
[tex]\Rightarrow (x-\frac{2}{3})=\pm \sqrt{\frac{10}{9}}[/tex]
[tex]\Rightarrow (x)=\frac{2}{3} \pm {\frac{\sqrt{10}}{3}[/tex]
Splitting the plus or minus sign gives
[tex]x=\frac{2- \sqrt{10}} {3}[/tex]
or
[tex]x=\frac{\sqrt{10}+2} {3}[/tex]
[tex]x=\frac{2-\sqrt{10}} {3}[/tex]
or
[tex]x=\frac{\sqrt{10}+2} {3}[/tex]
We have
[tex]3x^2-4x-2=0[/tex]
Since we cannot factor easily, we complete the square.
Adding 2 to both sides give,
[tex]3x^2-4x=2[/tex]
Dividing through by 3 gives
[tex]x^2-\frac{4}{3}x= \frac{2}{3}[/tex]
Adding [tex](-\frac{2}{3})^2[/tex] to both sides gives
[tex]x^2-\frac{4}{3}x+(-\frac{2}{3})^2= \frac{2}{3}+(-\frac{2}{3})^2[/tex]
The expression on the Left Hand side is a perfect square.
[tex](x-\frac{2}{3})^2= \frac{2}{3}+\frac{4}{9}[/tex]
[tex]\Rightarrow (x-\frac{2}{3})^2= \frac{10}{9}[/tex]
[tex]\Rightarrow (x-\frac{2}{3})=\pm \sqrt{\frac{10}{9}}[/tex]
[tex]\Rightarrow (x)=\frac{2}{3} \pm {\frac{\sqrt{10}}{3}[/tex]
Splitting the plus or minus sign gives
[tex]x=\frac{2- \sqrt{10}} {3}[/tex]
or
[tex]x=\frac{\sqrt{10}+2} {3}[/tex]
Answer:
[tex]x = \frac{2}{3} + \frac{\sqrt{10} }{3} , x = \frac{2}{3} - \frac{\sqrt{10} }{3}[/tex]
Step-by-step explanation:
Multiplying the coefficient of x by the constant to get:
3 x (-2) = -6
Find factors of -6 that equal the middle term -4.
Since, no such factors can be found so we can solve the equation by completing the square.
To complete the square, divide the equation by the coefficient of x^2 which is 3 to get:
[tex]x^{2} - \frac{4}{3} x - \frac{2}{3} = 0[/tex]
[tex]x^{2} - \frac{4}{3} x = \frac{2}{3}[/tex]
Now divide the coefficient of x by 2 and add the square of the result to both sides of the equation:
[tex]x^{2} - \frac{4}{3} x + (-\frac{2}{3} )^{2} = \frac{2}{3} + (-\frac{2}{3} )^{2}[/tex]
[tex](x - \frac{2}{3} )^2 = \frac{2}{3} + \frac{4}{9}[/tex]
[tex](x - \frac{2}{3} )^2 = \frac{4}{9}[/tex]
[tex]\sqrt{(x - \frac{2}{3} )^2} = \sqrt{\frac{4}{9} }[/tex]
[tex]x - \frac{2}{3} = \sqrt{\frac{10}{9} }[/tex] , [tex]x - \frac{2}{3} = -\sqrt{\frac{10}{9} }[/tex]
[tex]x = \frac{2}{3} + \frac{\sqrt{10} }{3} , x = \frac{2}{3} - \frac{\sqrt{10} }{3}[/tex]