Help! Brainliest!!! 20 points!!! PLEASE!

Answer:
[tex]-8x^{3} +4x^{2} -24x+12[/tex]
Step-by-step explanation:
Plug the equations in.
[tex]2x-1=f,[/tex] and [tex]x^{2} +3=g[/tex]
[tex](2x-1)(x^{2} +3) = 2x^{3} -x^{2} +6x-3[/tex]
Multiply that by -4.
[tex](2x^{3} -x^{2} +6x-3)(-4)=-8x^{3} +4x^{2} -24x+12[/tex]
Thus, the answer is [tex]-8x^{3} +4x^{2} -24x+12[/tex]
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