Question

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Answer 1

1.原式=[（3x+3)/（x+1)(x-1)-(x-1）/（x+1)(x-1)]-x/(x+1)(x-1)]

=（2x+4）/（x方-1)/[x/(x方-1）

=（2x+4)/x

=2+4/x

当x=根号2时

原式=2+（4倍根号2）/2

=2+2倍根号2

2原式=(100-99)（100+99)+.+(2+1)(2-1)

=100+99+98+.2+1

=5050