Question Number 71983 by device4438043516@gmail.com last updated on 23/May/20
$$ \\ $$
Answered by Henri Boucatchou last updated on 23/Oct/19
$$\boldsymbol{{d}}\left(\boldsymbol{{e}}^{\boldsymbol{{vlnu}}} \right)\:=\:\boldsymbol{{u}}^{\boldsymbol{{v}}} \:\boldsymbol{{d}}\left(\boldsymbol{{vlnu}}\right) \\ $$$$\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:\:=\:\boldsymbol{{u}}^{\boldsymbol{{v}}} \:\left(\boldsymbol{{lnu}}\:\boldsymbol{{dv}}\:+\:\boldsymbol{{v}}\frac{\boldsymbol{{du}}}{\boldsymbol{{u}}}\right) \\ $$
Commented by Henri Boucatchou last updated on 23/Oct/19
$$\boldsymbol{{Thank}}'\boldsymbol{{s}},\:\boldsymbol{{you}}'\boldsymbol{{re}}\:\boldsymbol{{welcome}} \\ $$