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\(\int_2^{+\infty} \frac{ e^t\,d t}{(e^{2t}-5e^t+6)(e^t-1)} = \ln\biggl( \frac{ e^2-2}{\sqrt{e^4-4e^2+3}} \biggr)\)
\(\int_0^{+\infty} \frac{ d t}{\ch^4t+\sh^4t} = \frac{ \ln(\sqrt2+1)}{\sqrt2}\)
\(\int_2^{+\infty} \frac{ e^t\,d t}{(e^{2t}-5e^t+6)(e^t-1)} = \ln\biggl( \frac{ e^2-2}{\sqrt{e^4-4e^2+3}} \biggr)\)
\(\int_0^{+\infty} \frac{ d t}{\ch^4t+\sh^4t} = \frac{ \ln(\sqrt2+1)}{\sqrt2}\)