1.
a) (8a-3a²+1) -(a-3a²) = 8a-3a²+1-a+3a²=7a+1
б) 16a³ -2a²(8a-3) = 16a³-16a³+6a²=6a²
в) 2ab(a+b)-ab(a-b) = 2a²b+2ab²-a²b+ab²=a²b+3ab² = a²b-ab² =ab(a-b)
г) (x³+1,3x² -2x) -(1.3x+2x²) = x³+1,3x² -2x-1,3x-2x²= x³-0,7x²-2x-1
2.
а) 14xy +21y² = 7y(2x+3y)
б) 3y³-6
= 3y³(1-2y³)
в) 8
b² -12a²b³+4a² =4a²(2a²b²-2b³+1)
г) x(y-5)-6(5-y) = x(y-5)+6(y-5) = (x+6)(y-5)