If the function \( f(x)=2x^3-9ax^2+12a^2x+1, \ a>0 \) has a local maximum at \( x=\alpha \) and a local minimum at \( x=\alpha^2 \), then \( \alpha \) and \( \alpha^2 \) are the roots of the equation:
\( 8x^2+6x-1=0 \)
\( x^2+6x+8=0 \)
\( x^2-6x+8=0 \)
\( 8x^2-6x+1=0 \)