[考点]
实数的运算,非零数的零指数幂,整式的混合运算,负整数指数幂,
[答案]
(1)4;
(2)﹣60xy;
(3)3xy4;
(4)a2﹣4b2+12bc﹣9c2.
[解析]
解:(1)
=1+4﹣1
=4;
(2)(3x﹣5y)2﹣(3x+5y)2
=[(3x﹣5y)﹣(3x+5y)]×[(3x﹣5y)+(3x+5y)]
=(﹣10y)×(6x)
=﹣60xy;
(3)(3xy)2⋅(﹣4xy3)÷(﹣12x2y)
=9x2y2⋅(﹣4xy3)÷(﹣12x2y)
=﹣36x3y5÷(﹣12x2y)
=3x3﹣2y5﹣1
=3xy4;
(4)(a﹣2b+3c)(a+2b﹣3c)
=[a﹣(2b﹣3c)]×[a+(2b﹣3c)]
=a2﹣(2b﹣3c)2
=a2﹣(4b2﹣12bc+9c2)
=a2﹣4b2+12bc﹣9c2.
[点评]
本题考查了"实数的运算,非零数的零指数幂,整式的混合运算,负整数指数幂,",属于"综合题",熟悉题型是解题的关键。