(1)原式=(-5+6)X+(-1+9)Y
=X+8Y
(2)原式=3A-2-3A+15
=0-2+15
=13
(3)原式=6A²B-7A²B+5AB²-4AB²
=-A²B+AB²
=AB(B-A)
(4)原式=4X²-6X+2X-3-2X²
=2X²-4X-3
(1)原式=(-5+6)X+(-1+9)Y
=X+8Y
(2)原式=3A-2-3A+15
=0-2+15
=13
(3)原式=6A²B-7A²B+5AB²-4AB²
=-A²B+AB²
=AB(B-A)
(4)原式=4X²-6X+2X-3-2X²
=2X²-4X-3