The sum of all real roots of equation $\left( e ^ { 2 x } - 4 \right) \left( 6 e ^ { 2 x } - 5 e ^ { x } + 1 \right) = 0$ is (1) $\ln 4$ (2) $- \ln 3$ (3) $\ln 3$ (4) $\ln 5$
The sum of all real roots of equation $\left( e ^ { 2 x } - 4 \right) \left( 6 e ^ { 2 x } - 5 e ^ { x } + 1 \right) = 0$ is\\
(1) $\ln 4$\\
(2) $- \ln 3$\\
(3) $\ln 3$\\
(4) $\ln 5$