数学题(多项式的乘法) 求.现在.(1)(3x+2)(x-1)-(x-1)(2x+3)(2)(2x-y)(x-2y)-2(x-y)(x+y3.先化简,再求值:x(x+2)-(x+1)(x-1)4.若在(mx2+nx+4)(x-2)的积中不含x2项和x项,求m、n.
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![数学题(多项式的乘法) 求.现在.(1)(3x+2)(x-1)-(x-1)(2x+3)(2)(2x-y)(x-2y)-2(x-y)(x+y3.先化简,再求值:x(x+2)-(x+1)(x-1)4.若在(mx2+nx+4)(x-2)的积中不含x2项和x项,求m、n.](/uploads/image/z/5253348-12-8.jpg?t=%E6%95%B0%E5%AD%A6%E9%A2%98%EF%BC%88%E5%A4%9A%E9%A1%B9%E5%BC%8F%E7%9A%84%E4%B9%98%E6%B3%95%EF%BC%89+%E6%B1%82.%E7%8E%B0%E5%9C%A8.%EF%BC%881%EF%BC%89%EF%BC%883x%2B2%29%28x-1%29-%28x-1%29%282x%2B3%29%282%29%282x-y%29%28x-2y%29-2%28x-y%29%28x%2By3.%E5%85%88%E5%8C%96%E7%AE%80%2C%E5%86%8D%E6%B1%82%E5%80%BC%EF%BC%9Ax%28x%2B2%29-%28x%2B1%29%28x-1%294.%E8%8B%A5%E5%9C%A8%28mx2%2Bnx%2B4%29%28x-2%29%E7%9A%84%E7%A7%AF%E4%B8%AD%E4%B8%8D%E5%90%ABx2%E9%A1%B9%E5%92%8Cx%E9%A1%B9%2C%E6%B1%82m%E3%80%81n.)
数学题(多项式的乘法) 求.现在.(1)(3x+2)(x-1)-(x-1)(2x+3)(2)(2x-y)(x-2y)-2(x-y)(x+y3.先化简,再求值:x(x+2)-(x+1)(x-1)4.若在(mx2+nx+4)(x-2)的积中不含x2项和x项,求m、n.
数学题(多项式的乘法) 求.现在.
(1)(3x+2)(x-1)-(x-1)(2x+3)
(2)(2x-y)(x-2y)-2(x-y)(x+y
3.先化简,再求值:x(x+2)-(x+1)(x-1)
4.若在(mx2+nx+4)(x-2)的积中不含x2项和x项,求m、n.
数学题(多项式的乘法) 求.现在.(1)(3x+2)(x-1)-(x-1)(2x+3)(2)(2x-y)(x-2y)-2(x-y)(x+y3.先化简,再求值:x(x+2)-(x+1)(x-1)4.若在(mx2+nx+4)(x-2)的积中不含x2项和x项,求m、n.
(1)(3x+2)(x-1)-(x-1)(2x+3)
=3x^2-x-2-(2x^2+x-3)=x^2-2x+1
(2)(2x-y)(x-2y)-2(x-y)(x+y
=2x^2-5xy+2y^2-2(x^2-y^2)=-5xy+4y^2
3.x(x+2)-(x+1)(x-1)
=x^2+2x-(x^2-1)=2x+1
4.若在(mx2+nx+4)(x-2)的积中不含x2项和x项,求m、n.
(mx2+nx+4)(x-2)=m x^3+(n-2m)x^2+(4-2n)x-8
n-2m=0
4-2n=0
n=2,m=1
1)(3x+2)(x-1)-(x-1)(2x+3)
=3x^2-x-2-(2x^2+x-3)=x^2-2x+1
(2)(2x-y)(x-2y)-2(x-y)(x+y
=2x^2-5xy+2y^2-2(x^2-y^2)=-5xy+4y^2
3.x(x+2)-(x+1)(x-1)
=x^2+2x-(x^2-1)=2x+1
4.若在(mx2+nx+4)(x...
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1)(3x+2)(x-1)-(x-1)(2x+3)
=3x^2-x-2-(2x^2+x-3)=x^2-2x+1
(2)(2x-y)(x-2y)-2(x-y)(x+y
=2x^2-5xy+2y^2-2(x^2-y^2)=-5xy+4y^2
3.x(x+2)-(x+1)(x-1)
=x^2+2x-(x^2-1)=2x+1
4.若在(mx2+nx+4)(x-2)的积中不含x2项和x项,求m、n。
(mx2+nx+4)(x-2)=m 希望能帮助您
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1.1-2x+X2 2.4Y2-5XY 3.2x+1 4.m=1,n=-2