f(x)=|log3(x)|,若f(a)>f(2),求正数a的取值范围RT答案是a>2 or 0

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f(x)=|log3(x)|,若f(a)>f(2),求正数a的取值范围RT答案是a>2 or 0

f(x)=|log3(x)|,若f(a)>f(2),求正数a的取值范围RT答案是a>2 or 0
f(x)=|log3(x)|,若f(a)>f(2),求正数a的取值范围
RT
答案是a>2 or 0

f(x)=|log3(x)|,若f(a)>f(2),求正数a的取值范围RT答案是a>2 or 0
f(2)=|log3(2)|
2>1,所以log3(2)>0
所以f(2)=log3(2)
|log3(x)|>log3(2)
所以log3(x)>log3(2)或log3(x)1,
所以log3(x)是增函数
log3(x)>log3(2)
所以x>2
log3(x)