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Question Number 27789 by abdo imad last updated on 14/Jan/18
find  lim_(x−>0) (1+sinx)^(1/x)   .
$${find}\:\:{lim}_{{x}−>\mathrm{0}} \left(\mathrm{1}+{sinx}\right)^{\frac{\mathrm{1}}{{x}}} \:\:. \\ $$
Commented by abdo imad last updated on 15/Jan/18
we have (1+sinx)^(1/x)  = e^((1/x)ln(1+sinx))   but   for x∈V(0)  sinx∼x and  ln(1+sinx)∼ln(1+x)∼x⇒  ((ln(1+sinx))/x) ∼1⇒  lim_(x−>0)  (1+sinx)^(1/x) =e .
$${we}\:{have}\:\left(\mathrm{1}+{sinx}\right)^{\frac{\mathrm{1}}{{x}}} \:=\:{e}^{\frac{\mathrm{1}}{{x}}{ln}\left(\mathrm{1}+{sinx}\right)} \\ $$$${but}\:\:\:{for}\:{x}\in{V}\left(\mathrm{0}\right)\:\:{sinx}\sim{x}\:{and} \\ $$$${ln}\left(\mathrm{1}+{sinx}\right)\sim{ln}\left(\mathrm{1}+{x}\right)\sim{x}\Rightarrow \\ $$$$\frac{{ln}\left(\mathrm{1}+{sinx}\right)}{{x}}\:\sim\mathrm{1}\Rightarrow\:\:{lim}_{{x}−>\mathrm{0}} \:\left(\mathrm{1}+{sinx}\right)^{\frac{\mathrm{1}}{{x}}} ={e}\:. \\ $$
Commented by prakash jain last updated on 16/Jan/18
thanks. your question and solution  are great learning experience
$$\mathrm{thanks}.\:\mathrm{your}\:\mathrm{question}\:\mathrm{and}\:\mathrm{solution} \\ $$$$\mathrm{are}\:\mathrm{great}\:\mathrm{learning}\:\mathrm{experience} \\ $$
Commented by abdo imad last updated on 16/Jan/18
thsnk you friend  prakash...
$${thsnk}\:{you}\:{friend}\:\:{prakash}… \\ $$

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