高一数学：：：：：若关于X的方程：4^|x|-2^|x|+1-3=a，在[-3，3]上有解，求a的取值范围。
\u9ad8\u4e00\u6570\u5b66\uff0c\u82e5\u5173\u4e8ex \u7684\u65b9\u7a0b9\uff3ex+\uff084+a\uff093\uff3ex+4\uff1d0\u6709\u89e3\uff0c\u5219\u5b9e\u6570a\u7684\u53d6\u503c\u8303\u56f4\uff1f\u4ee43^x=y
y^2+(4+a)y+4=0
(4+a)^2-16>0
(4+a)^2>16
4+a>4\u62164+a<-4
a>0\u6216a<-8
\u53c8y=3^x>0
\u6240\u4ee5y1*y2=4>0\u4e14y1+y2=-(4+a)>0
a<-4
\u6240\u4ee5a<-8
\u5c06\u8868\u8fbe\u5f0f\u8f6c\u6362\u4e0b
x^2+(m-1)x+1=0
==>m=-x-1/x+1=-(x+1/x)+1 \uff080<x<2\uff09
\u6709\u5bf9\u53f7\u51fd\u6570\uff0c\u6211\u4eec\u77e5\u9053\uff0cx+1/x\u5728x=1\u65f6\u53d6\u5230\u6700\u5c0f\u503c2
\u6545-(x+1/x)+1<-2+1=-1
\u6240\u4ee5m<-1
先求2的X次方
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