f(x)=(x+1)^1/x.
Calculate lim f(x); x->infinity.
`lim_(x->oo) (x+1)^(1/x)`
` `This is in the indeterminate form infinity raised to zero. To find the limit we need to rewrite it into a from so that we can use L'Hopital's rule.
Lets say that this limit is equal to L. Take the natural log of both sides:
ln(L) = (1/x) ln(x +1)
Focusing only on the right side we get:
`lim_(x->oo) ln(x+1)/(x)`
`<span class="AM"> </span> <br>`
` `Now we're in an infinity / infinity form and can use L'Hopital's rule.
Take the derivative of the numerator and denominator to get:
`lim_(x->oo) ((1)/(x+1))/(1)`
This limit is equal to 0.
But we're not done yet!
Keep in mind that the original limit we're solving for is L. This 0 is actually ln(L). To solve for L, we need to undo the logarithm by using e.
So L = e^0 = 1.
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