问几道有关分式的数学题 ,

题目

问几道有关分式的数学题 ,
(1)
[(5xy)/(x²+xy)]*[(xy+y²)/(2x²y²)]^3
(2)
[(x^3-3x+4)/(x²+2x-3)]÷[(x²-16)/(x²+6x+9)]
(3)
(x²+x-3)/(x²+x-2)+1=(2x²+4x+1)/(x²+2x+1)
(4)
已知a²+4a+1=0 ,且(a^4+ma²+1)/(2a^3+ma²+2a)=3 ,试确定m 的值.
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额,写得好的我会加分的说,

答案

1 (5xy)/(x²+xy)=5y/(x+y) (xy+y²)/(2x²y²)^3=(x+y)/(2x²y)^3 [5y/(x+y)]*[(x+y)/(2x²y)]^3=[5/(x+y)]*[(x+y)^3/(2x^6y²)]=5*(x+y)^2/(8x^6y²)2 x^3...