Answer:
-5x^6+5x^5+6x^4-6x^3
Step-by-step explanation:
[tex]\left(6-5x^2\right)\left(x^4-x^3\right)\\\\\mathrm{Apply\:FOIL\:method}:\\\quad \left(a+b\right)\left(c+d\right)=ac+ad+bc+bd\\\\a=6,\:b=-5x^2,\:c=x^4,\:d=-x^3\\\\=6x^4+6\left(-x^3\right)+\left(-5x^2\right)x^4+\left(-5x^2\right)\left(-x^3\right)\\\\\mathrm{Apply\:minus-plus\:rules}\\+\left(-a\right)=-a,\:\:\left(-a\right)\left(-b\right)=ab\\\\=6x^4-6x^3-5x^4x^2+5x^3x^2\\\\Simplify\\\\=-5x^6+5x^5+6x^4-6x^3[/tex]
