for (x+1) and (x+2) be a factor of given polynomialp(x) , they must be its roots. and
hence according to remainder theorem p(-1) and p(-2) must be 0,
solving these 2 simentanous equation.
so b= 10 and a is 1
and polynomial becomes x^3-x^2-10x-8=0
since product of roots is 8(-d/a) and 2 roots are -1 and -2 last root must be 4 so factor is (x-4)
you could also go for long division.!!!
A squared number is what you get when you multiply a number by itself; for example, 4 is the square of 2, because 2x2=4, and 25 is the square of 5, because 5x5=25, and so on. A cubed number is what you get when you multiply a number by itself TWICE; for example, if you do 2x2x2, first 2x2=4, and then this multipled by 2 again =8, so 8 is the CUBE of 2. 4x4=8, and 8 multiplied by 4 again=32, so 32 is the CUBE of 4. Numbers that you multiply to get their square or cube root