绝对值不等式解法,,填空,,进下...

解：∣f(x)∣＜g(x) <==> -g(x)＜f(x)＜g(x)

∣f(x)∣＞g(x) <==> f(x)＞g(x)或f(x)＜-g(x)
f(x)除以g(x)＞0<==> f(x)g(x)＞0
f(x)除以g(x)＜0<==> f(x)g(x)＜0
f(x)g(x)＞0<==> f(x)＞0，g(x)＞0或 f(x)＜0，g(x)＜0
f(x)g(x)＜0<==> f(x)＞0，g(x)＜0或 f(x)＜0，g(x)＞0

-g(x)小于f(x)小于g(x) f(x)大于g(x)或f(x)小于-g(x)
f(x)*g(x)大于0 f(x)*g(x)小于0
f(x)g(x)同号，f(x)g(x)异号

1.-g(x)＜f(x) ＜ g(x)
2.f(x)> g(x)或f(x)<- g(x)
3.f(x)g(x)＞0
4.f(x)g(x)＜0
5.f(x)与g(x)同号
6.f(x)与g(x)异号

-g(x)<f(x)<g(x)
-g(x)>f(x)或g（x）<f(x)
g(x)不等于0时，有f(x)>0且g(x)>0，或f(x)<0且g(x)<0；g(x)=0无解
g(x)不等于0时，有f(x)<0且g(x)>0；或f(x)>0且g(x)<0；g(x)=0无解
f(x)>0且g(x)>0或f(x)<0且g(x)<0
f(x)<0且g(x)>0或f(x)>0且g(x)<0