Question 422550
The function {{{y= 2x^2+4x-2}}} is a parabola As we know the coordinates of the vertex are: 
             {{{ x= -b/2a = -4/2(2)}}}, { x =-1 } and 

              {{{y =2*(-1)^2+4*(-1)-2}}} , {y = -4}

 The vertex of parabola is the point (-1, -4)

 {{{graph( 400, 400, -5, 5, -5, 5, 2x^2+4x-2)}}}.