f(x)=(log2 x/2)(log2 x/4) (根号2 ≤ x ≤ 8) 求值域..
问题描述:
f(x)=(log2 x/2)(log2 x/4) (根号2 ≤ x ≤ 8) 求值域..
答
将对数化成除式的形式,即:(log2x)/(log2 2) (log2x)/(log2 4)化简等于2倍(log2x)的平方!根据x的条件知,当x为根号2时最小为1,当为8时值最大为6.明白?