Find the value of g, given that 8x2+2x+g=0 and 2x2+gx+1=0 have a common root?
OPTION E
To find the common root, equate the two equations
2x2+gx+1=8x2+2x+g
-6x2+x(g-2)+(1-g)=0
Now find the discriminant of this equation and equate that to 0(D=0 means that the roots are equal and there exists a single root, acording to the question also, there is a single root which is common, hence D=0)
we will get it as : g2 - 28g +28 = 0
Check with answer options at this stage
None of the values of x is being satisfied, hence option e.