2X³-X²-4X+3
= X³-X²+X³-X+3-3X
= X²(X-1)+X(X²-1)-3(X-1)
= X²(X-1)+X(X-1)(X+1)-3(X-1)
= (X-1)(X²+X²+X-3)
= (X-1)(2X²+X-3)
=(X-1)(2X+3)(X-1)