\[\boxed{\mathbf{52.}}\]
\[\textbf{а)}\ \left( x - \log_{3}75 \right)\left( x - \log_{2}22 \right) =\]
\[= 0\]
\[x \in \lbrack 3;4\rbrack.\]
\[1)\ x - \log_{3}75 = 0\]
\[x = \log_{3}75\]
\[\log_{3}27 < \log_{3}75 < \log_{3}81\]
\[3 < \log_{3}75 < 4.\]
\[2)\ x - \log_{2}22 = 0\]
\[x = \log_{2}22\]
\[\log_{2}16 < \log_{2}22\]
\[4 < \log_{2}22.\]
\[Ответ:x = \log_{3}75.\]
\[\textbf{б)}\ \left( x - \log_{2}17 \right)\left( x - \log_{2}71 \right) =\]
\[= 0\]
\[x \in \lbrack 4;5\rbrack.\]
\[1)\ x - \log_{2}17 = 0\]
\[x = \log_{2}17\]
\[\log_{2}16 < \log_{2}17 < \log_{2}32\]
\[4 < \log_{2}17 < 5.\]
\[2)\ x - \log_{2}71 = 0\]
\[x = \log_{2}71\]
\[\log_{2}64 < \log_{2}71\]
\[6 < \log_{2}71.\]
\[Ответ:x = \log_{2}17.\]