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,