6.|f(x)|>a (a>0)⇔______________________. 7.|f(x)|g(x)⇔_________________________. 9.|f(x)|<|g(x)|⇔______________. 10.|f(x)|>|g(x)|⇔______________.

f(x)>a或f(x)<－a

－g(x)

f(x)>g(x)或f(x)<－g(x)

f2(x)

f2(x)>g2(x)