1.3x²-5x+2
=(3x+1)(x-2)
2.x³-2x²-3x
=x(x²-2x-3)
=x(x-3)(x+1)
3.x²-6x-16
=(x-8)(x+2)
4.m²+4mn-12n²
=(m+6n)(m-2n)