Question 898077
{{{a+b<0}}}
{{{a<-b}}}
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{{{a*sqrt(b)<0}}}
Since {{{sqrt(b)>=0}}} then only when {{{a<0}}}
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{{{a/b<0}}} when either {{{a<0}}} and {{{b>0}}} or {{{a>0}}} and {{{b<0}}}
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{{{ab^3<0}}} when either {{{a<0}}} and {{{b>0}}} or {{{a>0}}} and {{{b<0}}}