性趣屋:八年级数学分式题(重点是过程)

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化简下列分式.
⑴(1/x+2)-(4x/4-x^2)+(2/2-x)
⑵〖(2x/x-3)-(x/x+3)〗×(x^2-9/x)
我有这两个题的答案但没有过程,⑴的答案是3/x+2,⑵的答案是x+9!谁能告诉我过程!

⑴(1/x+2)-(4x/4-x^2)+(2/2-x)
=(x-2+4x-4-2x)/(x^2-4)
=3(x-2)/(x^2-4)
=3/(x+2)

(2)
〖(2x/x-3)-(x/x+3)〗×(x^2-9/x)
=(2x^2+6x-x^2+3x)/(x^2-9)*(x^-9)/x
=(x^2+9x)/x
=x+9

⑴(1/x+2)-(4x/4-x^2)+(2/2-x)
=(x-2+4x-4-2x)/(x^2-4)
=3/(x+2)

(2)
〖(2x/x-3)-(x/x+3)〗×(x^2-9/x)
=(2x^2+6x-x^2+3x)/(x^2-9)*(x^-9)/x
=x+9

3/x+2