初一下数学(1)(0.2x-0.3)(0.2+0.3) (2) (mn-3n)(mn+3n) (3) (-2x+3y)(
来源:学生作业帮 编辑:搜搜考试网作业帮 分类:数学作业 时间:2024/07/06 21:05:34
初一下数学
(1)(0.2x-0.3)(0.2+0.3)
(2) (mn-3n)(mn+3n)
(3) (-2x+3y)(-2x-3y)
(4) (-四分之一x-2y)(-四分之一+2y)
(15) x^+(y-x)(y+x)
^表示平方 要过程 给分
(1)(0.2x-0.3)(0.2+0.3)
(2) (mn-3n)(mn+3n)
(3) (-2x+3y)(-2x-3y)
(4) (-四分之一x-2y)(-四分之一+2y)
(15) x^+(y-x)(y+x)
^表示平方 要过程 给分
![初一下数学(1)(0.2x-0.3)(0.2+0.3) (2) (mn-3n)(mn+3n) (3) (-2x+3y)(](/uploads/image/z/13046373-45-3.jpg?t=%E5%88%9D%E4%B8%80%E4%B8%8B%E6%95%B0%E5%AD%A6%EF%BC%881%EF%BC%89%EF%BC%880.2x-0.3%29%280.2%2B0.3%29+%282%29+%28mn-3n%29%28mn%2B3n%29+%283%29+%28-2x%2B3y%29%28)
(1)(0.2x-0.3)(0.2x+0.3)=(0.2x)²-0.3²=0.04x²-0.09
(2) (mn-3n)(mn+3n)=(mn)²-(3n)²=m²n²-9n²
(3) (-2x+3y)(-2x-3y)=(-2x)²-(3y)²=4x²-9y²
(4) (-四分之一x-2y)(-四分之一x+2y)=(-四分之一x)²-(2y)²=十六分之一x²-4y²
(15) x^2+(y-x)(y+x)=x²+y²-x²=y²
(2) (mn-3n)(mn+3n)=(mn)²-(3n)²=m²n²-9n²
(3) (-2x+3y)(-2x-3y)=(-2x)²-(3y)²=4x²-9y²
(4) (-四分之一x-2y)(-四分之一x+2y)=(-四分之一x)²-(2y)²=十六分之一x²-4y²
(15) x^2+(y-x)(y+x)=x²+y²-x²=y²
初一下数学(1)(0.2x-0.3)(0.2+0.3) (2) (mn-3n)(mn+3n) (3) (-2x+3y)(
已知:单项式mn满足2x(M+3x)=6x²y²+N,求MN
已知mn^2=-5,求-mn(m^3n^7-m^2n^5-n)的值 已知2x的3m+1次方y的2n次方与6x的n-6次方
(1).x^2-xy+x (2).m^2n-mn^2+mn (3).9x^3y^3-21x^3y^2+12x^2y^2
已知单项式M、N满足2x(M+3x)=6x^2y^2+N,求MN
初一数学绝对值|m+n-2|+(mn+3)平方=0求m=?n=?
计算:(x/y^3)^-2 计算:m+n/m-n除以mn+m^2/2m
提取公因式法 有分6(m-n)³-12(n-m)²2(y-x)²+3(x-y)mn(m-n
3m平方n平方+12mn+x(mn+2)平方
1.(因式分解)m*m/9-mn/3+n*n/4.2.已知x*x+y*y-2x+1=0,求xy=________.
已知x+y=负三,求(x+y)²-3x-3y+2的值 已知m+n=2mn,求代数式3m-2mn+3n分之m+2
1.如果线段MN平行y轴,且M(3,-5),N(x,2)则x=( )