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计算下列各式1.(2X+Y)(3a+2B)2.(4X-3)(X+4)3.(3X+2Y)(2X-3Y)4.(3Y-1)(2Y-3)+(6Y-5)(Y-4)

题目详情
计算下列各式
1.(2X+Y)(3a+2B)
2.(4X-3)(X+4)
3.(3X+2Y)(2X-3Y)
4.(3Y-1)(2Y-3)+(6Y-5)(Y-4)
▼优质解答
答案和解析
1.(2X+Y)(3a+2B)
=6aX+4BX+3aY+2BY
2.(4X-3)(X+4)
=4X^2+16X-3X-12
=4X^2+13X-12
3.(3X+2Y)(2X-3Y)
=6X^2-9XY+4XY-6Y^2
=6X^2-5XY-6Y^2
4.(3Y-1)(2Y-3)+(6Y-5)(Y-4)
=6Y^2-9Y-2Y+3+6Y^2-24Y-5Y+20
=12Y^2-35Y+23
=(12Y-1)(Y-23)