Question 1045307
I could begin with {{{(a/b)^(a/b)-a^(a/b-1)=a^(a/b)/b^(a/b)-a^(a/b-1)}}} ,
but that gets rendered in a way that is hard to read,
so I will write the the same expression in a way that it can be read: {{{(a/b)^(a/b)-a^(a/b-1)}}}{{{"="}}}{{{a^"a/b"/b^"a/b"}}}{{{-a^("a/b"-1)}}}

From the "If {{{a^b=b^a}}} " statement, we get
{{{a^b=b^a}}} ---> {{{(a^b)^(1/b)=(b^a)^(1/b)}}} ---> {{{a^"b/b"=b^"a/b"}}} --->{{{a=b^"a/b"}}} = the denominator in the expression above.
With that,
{{{(a/b)^(a/b)-a^(a/b-1)}}}{{{"="}}}{{{a^"a/b"/b^"a/b"}}}{{{-a^("a/b"-1)}}}{{{"="}}}{{{a^"a/b"/a}}}{{{-a^("a/b"-1)}}}{{{"="}}}{{{a^("a/b"-1)}}}{{{-a^("a/b"-1)}}}{{{"="}}}{{{highlight(0)}}}