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Question Number 182644 by mr W last updated on 12/Dec/22
solve for x>0  (1+(1/x))^x >(5/2)
$${solve}\:{for}\:{x}>\mathrm{0} \\ $$$$\left(\mathrm{1}+\frac{\mathrm{1}}{{x}}\right)^{{x}} >\frac{\mathrm{5}}{\mathrm{2}} \\ $$
Commented by Frix last updated on 12/Dec/22
Obviously x>1
$$\mathrm{Obviously}\:{x}>\mathrm{1} \\ $$
Commented by mr W last updated on 12/Dec/22
it should not be a too special case,  therefore i have modified the   question.
$${it}\:{should}\:{not}\:{be}\:{a}\:{too}\:{special}\:{case}, \\ $$$${therefore}\:{i}\:{have}\:{modified}\:{the}\: \\ $$$${question}. \\ $$
Commented by Frix last updated on 12/Dec/22
x=(1/t)  t+1>((5/2))^t   This should be possible with LambertW
$${x}=\frac{\mathrm{1}}{{t}} \\ $$$${t}+\mathrm{1}>\left(\frac{\mathrm{5}}{\mathrm{2}}\right)^{{t}} \\ $$$$\mathrm{This}\:\mathrm{should}\:\mathrm{be}\:\mathrm{possible}\:\mathrm{with}\:\mathrm{LambertW} \\ $$
Commented by MJS_new last updated on 12/Dec/22
I get  t+1=q^t  ⇒ t=−(1+((W(−((ln q)/q)))/(ln q)))  q=(5/2) ⇔  { ((t=0)),((t≈.188114820)) :} ⇒ x≈5.31590237
$$\mathrm{I}\:\mathrm{get} \\ $$$${t}+\mathrm{1}={q}^{{t}} \:\Rightarrow\:{t}=−\left(\mathrm{1}+\frac{{W}\left(−\frac{\mathrm{ln}\:{q}}{{q}}\right)}{\mathrm{ln}\:{q}}\right) \\ $$$${q}=\frac{\mathrm{5}}{\mathrm{2}}\:\Leftrightarrow\:\begin{cases}{{t}=\mathrm{0}}\\{{t}\approx.\mathrm{188114820}}\end{cases}\:\Rightarrow\:{x}\approx\mathrm{5}.\mathrm{31590237} \\ $$
Commented by mr W last updated on 13/Dec/22
thanks sirs!
$${thanks}\:{sirs}! \\ $$

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