[tex]\displaystyle\bf\\y=(x^{3} +4)(x^{2} -3)\\\\y'=(x^{3} +4)'\cdot(x^{2} -3)+(x^{3} +4)\cdot(x^{2} -3)'=\\\\=3x^{2} \cdot(x^{2} -3)+(x^{3} +4)\cdot 2x=3x^{4} -9x^{2} +2x^{4}+8x=\\\\=5x^{4} -9x^{2} +8x[/tex]