x减3y=0,求(X的平方减Y的平方)分之(4XY) 减 (X减Y)分之(X+Y)的值
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:2024/08/17 12:23:52
x减3y=0,求(X的平方减Y的平方)分之(4XY) 减 (X减Y)分之(X+Y)的值
![x减3y=0,求(X的平方减Y的平方)分之(4XY) 减 (X减Y)分之(X+Y)的值](/uploads/image/z/14905924-52-4.jpg?t=x%E5%87%8F3y%EF%BC%9D0%2C%E6%B1%82%28X%E7%9A%84%E5%B9%B3%E6%96%B9%E5%87%8FY%E7%9A%84%E5%B9%B3%E6%96%B9%29%E5%88%86%E4%B9%8B%284XY%29+%E5%87%8F+%28X%E5%87%8FY%29%E5%88%86%E4%B9%8B%28X%2BY%29%E7%9A%84%E5%80%BC)
解
x-3y=0
x=3y
(4xy)/(x²-y²)-(x+y)/(x-y)
=(4xy)/(x+y)(x-y)-(x+y)²/(x-y)(x+y)
=(4xy-x²-2xy-y²)/(x-y)(x+y)
=-(x-y)²/(x-y)(x+y)
=-(x-y)/(x+y)
=-(3y-y)/(3y+y)
=-1/2
直接代入更简单
原式
=4xy/(x²-y²)-(x+y)/(x-y)
=12y²/(9y²-y²)-(3y+y)/(3y-y)
=12/8-2
=3/2-2
=-1/2
x-3y=0
x=3y
(4xy)/(x²-y²)-(x+y)/(x-y)
=(4xy)/(x+y)(x-y)-(x+y)²/(x-y)(x+y)
=(4xy-x²-2xy-y²)/(x-y)(x+y)
=-(x-y)²/(x-y)(x+y)
=-(x-y)/(x+y)
=-(3y-y)/(3y+y)
=-1/2
直接代入更简单
原式
=4xy/(x²-y²)-(x+y)/(x-y)
=12y²/(9y²-y²)-(3y+y)/(3y-y)
=12/8-2
=3/2-2
=-1/2
x减3y=0,求(X的平方减Y的平方)分之(4XY) 减 (X减Y)分之(X+Y)的值
y分之x等于2分之1求x平方减xy加y平方分之x平方加2xy加y平方的值
已知y分之x等于2求x的平方+xy+6(y)分之x平方减xy+3(y)的平方的值
已知x-3y=0,求x平方减2xy+y平方分之2x+y乘以(x-y)的值
已知5x-4y=0,切xy≠0,求(x平方-y平方)分之(x平方+y平方)-(x-y)分之(x+y)的值
3x的平方减xy减4y的平方等于0 求x分之y等于多少.
x平方减五xy加六y的平方等于零.求y分之x等于.
y分之x等于3求x平方减y平方分之x平方加y平方减xy
已知;3X的平方+XY-2Y平方=0,求(X-Y分之X+Y)+Y平方-X平方分之4XY)除以X平方-9Y平方分之X平方+
已知x平方+3xy-4y平方=0,求x+2y分之x-2y的值
已知x的平方减7xy加y的平方等于0,求y分之x的值
X=根号3+1,Y=根号3-1.求X的平方-Y的平方分之X的平方减2XY+Y的平方