:(1)要使f1(x)与f2(x)有意义,则有要使f1(x)与f2(x)在给定区间[a+2,a+3]上有意义,等价于真数的最小值大于0即(2)f1(x)与f2(x)在给定区间[a+2,a+3]上是接近的|f1(x)–f2(x)|≤1≤1|loga[(x–3a)(x–a)]|≤1a≤(x–2a)2–a2≤对于任意x∈[a+2,a+3]恒成立设h(x)=(x–2a)2–a2,x∈[a+2,a+3]≤≤≤≤≤≤≤≥≥≥≥≥≤且其对称轴x=2a<2在区间[a+2,a+3]的左边当时,f1(x)与f2(x)在给定区间[a+2,a+3]上是接近的当<a<1时,f1(x)与f2(x)在给定区间[a+2,a+3]:(1)∵∴ 1分∵的解集中包含2和-2,∴
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