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运用立方和与立方差公式化简:(1)(y+3)(y2-3y+9);(2)(3+2y)(9-6y+4y2);(3)(5x-12y)(25x2+52xy+14y2);(4)(2x+1)(4x2+2x+1);(5)(2x-3y)(4x2+6xy+9y2);(6)(x2+y2)(x4-x2y2

题目详情
运用立方和与立方差公式化简:
(1)(y+3)(y2-3y+9);
(2)(3+2y)(9-6y+4y2);
(3)(5x-
1
2
y)(25x2+
5
2
xy+
1
4
y2);
(4)(2x+1)(4x2+2x+1);
(5)(2x-3y)(4x2+6xy+9y2);
(6)(x2+y2)(x4-x2y2+y4
▼优质解答
答案和解析
(1)(y+3)(y2-3y+9)
=y3-3y2+9y+3y2-9y+27
=y3+27;
(2)(3+2y)(9-6y+4y2
=27-18y+12y2+18y-12y2+8y3
=27+8y3
(3)(5x-
1
2
y)(25x2+
5
2
xy+
1
4
y2
=125x3+
25
2
x2y+
5
4
xy2-
25
2
x2y+
5
4
xy2-
1
8
y3
=125x3-
1
8
y3;
(4)(2x+1)(4x2+2x+1)
=8x3+4x2+2x+4x2+2x+1
=8x3+8x2+4x+1;
(5)(2x-3y)(4x2+6xy+9y2
=8x3+12x2y+18xy2-12x2y-18xy2-27y3
=8x3-27y3
(6)(x2+y2)(x4-x2y2+y4
=x6-x4y2+x2y4+x4y2-x2y4+y6
=x6+y6