contestada

help plsss

1/2x^2 =2
If x1 and x2 are the solutions to the equation above,
what is the value of x1 + x2?
A) 0
B) 1
C) 2
D) 4

Respuesta :

⭐ Development:

  • Having the expression, let's modify it so it becomes a 2nd degree equation:

[tex]\large {\text {$ \sf \cfrac{1}{2x^2} -2 = 0 $}}[/tex]

  • Now, we will multiply per 2x² both sides of equation...

[tex]\large {\text {$ \sf \cfrac{1}{2x^2}\cdot \:2x^2-2\cdot \:2x^2=0\cdot \:2x^2 $}[/tex]

                 [tex]\searrow[/tex]

                     [tex]\large {\text {$ \sf 1-4x^2=0$}}[/tex]

  • We have to write in standard form...

[tex]\large {\text {$ \sf -4x^2+1 = 0 $}}[/tex]

                                                                                                     

[tex]\large {\text{$\sf x=\cfrac{-b\pm\sqrt{b^2-4ac}}{2a} \quad\rightarrow\quad x=\cfrac{-0\pm\sqrt{0^2-4\cdot (-4) \cdot1} }{2\cdot (-4) } \:\rightarrow\:\: x=\cfrac{-0^2 \pm4}{2 \cdot(-4)} $}}[/tex]  

                                                                                                                         

                                                             [tex]\huge {\text {$ \sf \downarrow$}}[/tex]

                                                                                                         

           [tex]\large {\text {$\sf {\bf x_1} = \cfrac{-0+4}{2\left(-4\right)}= \cfrac{-1}{2} $}}[/tex]                        [tex]\large {\text {$\sf {\bf x_2 }=\cfrac{-0-4}{2\left(-4\right)} = \cfrac{1}{2} $}}[/tex]

  • At this point, we're going to add the values ​​of x₁ and x₂:

[tex]\large {\boxed {\boxed { \bf x_1 + x_2= -\cfrac{1}{2}+ \cfrac{1}{2} = 0} }}[/tex]

                                           [tex]\huge {\text {$ \it Alternative \: A $}}[/tex]

Ver imagen PiuzinhoDaTropa