Tìm x, biết: a) (x + 1)^3 + (x + 1) = 0; b) 8x^3 + 12x^2 + 6x + 1 = 0

Tìm x
a) (x+1)^3+(x+1)=0
b) 8x^3+12x^2+6x+1=0
c) 2(x+5)-x^2-5x=0