[tex]\bf \textit{exponential form of a logarithm}
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log_a  b=y \implies   a^y=  b\qquad\qquad 
%  exponential notation 2nd form
a^y=  b\implies log_a  b=y \\\\
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log_4(128)=\cfrac{7}{2}\qquad \implies \qquad 4^{\frac{7}{2}}=128[/tex]