Explain the Error in the Following $$\log _ { 6 } 8 - \log _ { 6 } \mathrm {~N} = \log _ { 6 } \left( 8 - \mathrm { N } ^ { 2 } \right.$$

Explain the error in the following: $$\log _ { 6 } 8 - \log _ { 6 } \mathrm {~N} = \log _ { 6 } \left( 8 - \mathrm { N } ^ { 2 } \right.$$