设f(x-1)=x²-3,则f(x)=？ 已知f（x-1/x)=x²+1/x²，则...
\u5df2\u77e5f\uff08x-(1/x\uff09)=x²+\uff081/x²\uff09\u5219f\uff083\uff09=?x-(1/x)=3\uff0c
\u6240\u4ee5\uff1ax²-2+1/x²=9\uff0c
\u6240\u4ee5\uff1ax²+1/x²=11\uff0c
\u6240\u4ee5\uff1af(3)=11
\u5df2\u77e5f\uff08x-1/x)=x²+1/x²\uff0c
=\uff08x-1/x\uff09²+2;
\u2234f(x)=x²+2;
\u5219\u51fd\u6570f\uff083\uff09=3²+2=9+2=11;
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\u5982\u679c\u672c\u9898\u6709\u4ec0\u4e48\u4e0d\u660e\u767d\u53ef\u4ee5\u8ffd\u95ee\uff0c\u5982\u679c\u6ee1\u610f\u8bb0\u5f97\u91c7\u7eb3
\u5982\u679c\u6709\u5176\u4ed6\u95ee\u9898\u8bf7\u91c7\u7eb3\u672c\u9898\u540e\u53e6\u53d1\u70b9\u51fb\u5411\u6211\u6c42\u52a9\uff0c\u7b54\u9898\u4e0d\u6613\uff0c\u8bf7\u8c05\u89e3\uff0c\u8c22\u8c22\u3002
\u795d\u5b66\u4e60\u8fdb\u6b65
方法较多，举例如下。
方法一
由题知f（x-1）=x²-3,
则f（x-1）=（x-1+1）²-3=（x-1）²+2（x-1）-2,
所以f（x）=x²+2x-2.
方法二
由题知f（x-1）=x²-3,
不妨设t=x-1,则x=1+t.
所以f（t）=（1+t）²-3=t²+2t-2.
因此f（x）=x²+2x-2.
如果没有算错的话
答案应该是
x^2+2x-2
解如下图所示
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