(adsbygoogle = window.adsbygoogle || []).push({}); 1.given the equation a(3x^{2}+2x+1)=4x-6x^{2}-4 with the solutions x_{1}and x_{2}

a) let a=0 without solving the equation calculate x_{1}^{-3}+x_{2}^{-3}

the correct answer is supposed to be -7/2

2. Relevant equations

x_{1}+x_{2}=-b/a

x_{1}*x_{2}=c/a

3. The attempt at a solution

The first thing I was that I put in "a" so,

0*(3x^{2}+2x+1)=4x-6x^{2}-4

0=4x-6x^{2}-4................... here I multiplied the whole equation by -1

0=6x^{2}-4x+4...........................here i divided the equation by 6

0=x^{2}-4/6x+46

then I used the equation

1/x_{1}^{3}+1/x_{2}^{3}=(1/x_{1}+1/x_{2})^{3}-3/x_{1}^{2}x_{2}-3/x_{2}^{2}x_{1}

This is where I have no idea how to continue.I'm not even sure that what I have written is correct .If someone could help me solve this,I would really appreciate it. Thanks for reading .

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# Quadratic equation

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