Remember one of the laws of logs: \(n{\log _a}x = {\log _a}{x^2}\) Another one of the laws are used here: \({\log _a}x + {\log _a}y = {\log _a}xy\) ...
\({\log _a}a = 1\) (since \({a^1} = a\)) so \({\log _7}7 = 1\) \({\log _a}1 = 0\) (since \({a^0} = 1\)) so \({\log _{20}}1 = 0\) \({\log _a}p + {\log _a}q = {\log _a ...