函数fx没给定义域是不是就是指定义域为r
,\u51fd\u6570fx\u7684\u5b9a\u4e49\u57df\u4e3aR,\u4e14x\u4e0d\u7b49\u4e8e1\u5f53x>1\u65f6\u30022-x<1\uff0cf\uff082-x\uff09=2\uff082-x\uff09^2-\uff082-x\uff09+1=2x^2-7x+7
\u56e0\u4e3af\uff08x+1\uff09\u4e3a\u5947\u51fd\u6570\uff0c\u6240\u4ee5f\uff08x+1\uff09=-f\uff08-x+1\uff09\uff0c
\u6240\u4ee5\u5f53x>1\u65f6\uff0cf\uff08x\uff09=f\uff08x-1+1\uff09=-f[-\uff08X-1\uff09+1]=-f\uff082-x\uff09=-2x^2+7x-7
1 f(0)=(b-1)/(a+2)=0 =>b=1
f(1)=-f(-1) => a=0
2 f(x)\u5728R\u4e0a\u662f\u51cf\u51fd\u6570
f(t^2-2t)+f(2t^2-k)\uff1c0 f(t^2-2t)< -f(2t^2-k)
f(t^2-2t)< f(k-2t^2)
t^2-2t>k-2t^2\u5bf9\u4e00\u5207t\u6210\u7acb
3t^2-2t-k>0\u5bf9\u4e00\u5207t\u6210\u7acb
=>delta = 4+12k<0
=> k<-1/3
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