UC知道数学算式题(数学高手进)
来源：百度知道 编辑：UC知道 时间：2024/06/05 13:38:25
(1)3x^2-[7x-(4x-3)-2x^2]
(2)(2xy-y)-(-y+yx)
(3)5(a^2b-3ab^2)-2(a^2b-7ab^2)
(4)11x^2+4x-1-x^2-4x-5
(5)(2x^4-4x^3y-2x^2y^2)-(x^4-2x^2y^2+y^3)+(-x^4+4x^3y-y^3)
要过程....注:x^2表示x的2次方,x^4表示x的4次方....
(2)(2xy-y)-(-y+yx)
(3)5(a^2b-3ab^2)-2(a^2b-7ab^2)
(4)11x^2+4x-1-x^2-4x-5
(5)(2x^4-4x^3y-2x^2y^2)-(x^4-2x^2y^2+y^3)+(-x^4+4x^3y-y^3)
要过程....注:x^2表示x的2次方,x^4表示x的4次方....
俺不是高手，俺问问是因式分解么？
(1)3x^2-[7x-(4x-3)-2x^2]
=3x^2-7x+4x-3+2x^2
=5x^2-3x-3
(2)(2xy-y)-(-y+yx)
=2xy-y+y-xy
=xy
(3)5(a^2b-3ab^2)-2(a^2b-7ab^2)
=5a^2b-15ab^2-2a^2b+14ab^2
=3a^2b-ab^2
(4)11x^2+4x-1-x^2-4x-5
=10x^2-6
(5)(2x^4-4x^3y-2x^2y^2)-(x^4-2x^2y^2+y^3)+(-x^4+4x^3y-y^3)
=2x^4-4x^3y-2x^2y^2-x^4+2x^2y^2-y^3-x^4+4x^3y-y^3
=-2y^3
看不懂
什么“x^2表示x的2次方,x^4表示x的4次方”