<p>I wasn't sure how to apply the integral test on (n+1)/n!<br>
1/x(lnx) and n/(2^n), anyone can show me the test for divergence?</p>
<p>I wasn’t sure how to apply the integral test on (n+1)/n!</p>
<p>Is that the quantity n (n) or the factorial of quantity n? (n!)?</p>
<p>You can’t integrate n!. Well, actually, you can using the Gamma function but eh, not important xD.</p>
<p>Sorry, i meant the integral test…</p>
<p>To apply the integral test, you need to be able to integrate the function…</p>
<p>how about integrate 1/x(lnx) and n/(2^n)?</p>
<p>xDD</p>
<p>That’s why I asked.</p>
<p>Integral=Integration…</p>
<p>Ok im sure if integrating the ‘n’ is BC type knowledge since im taking AB, but for this ‘1/x(lnx)’ is quite easy.</p>
<p>Since where intergrating 1/x(lnx) (if thats your question) you would use u-substitution.
u= ln(x)
du = 1/x dx (derivative)</p>
<p>substitute the u into the integral
u(du)
now integrate = u = ln(x)</p>
<p>^
That’s wrong.</p>
<p>u = ln x. du = 1/x</p>
<p>(1/u) du. –> ln u –> ln (ln x) + C. You can check by deriving it that you do indeed get the answer.</p>
<p>Xav, I think swimmer placed ln(x) on the numerator not the denominator. But if he did your right, if not them Im right. btw forgot to add C. Always forget that</p>