16x^5 - 8x^4 + x^3
x^3(16x^2 - 8x + 1)
x^3(4x -1)(4x-1)
.
4x^2 - x
x(4x - 1)
.
x^2 = x * x
.
For the x's (the ones by themselves) x^3 is the smallest thing that x^3, x, and x^2 go into.
For the (4x-1)'s, (4x-1)(4x-1) has enough (4x-1)'s to make (4x-1)(4x-1) or just (4x-1).
x^3(4x-1)(4x-1)
Answer: x^3 (4x-1)^2 which is the same thing as 16x^5 - 8x^4 + x^3