(x^3+1)`=3x^2
(-1/x-3x)`=-(x^(-1))`-3=1/(x^2)-3
(4x^4+√x)`=16x^3+1/(2√x)
(1/3x^3-2√x+5/x)`=x^2-1/√x+5x^(-1)=x^2-1/√x-5/x^2
((5x-4)(2x^4-7x+1))`=(5x-4)`(2x^4-7x+1)+(5x-4)(2x^4-7x+1)`=10x^4-35x+5+(5x-4)(8x^3-7)=10x^4-35x+5+40x^4-35x+32x^3-28=50x^4+32x^3-70x-23