If the sum of the series `sum_(n=0)^oor^n ,|r|<1i ss ,` then find the sum of the series `sum_(n=0)^oor^(2n)` .

If the sum of the series sum_(n=0)^(oo)r^(n),|r|<1 is s then find the sum of the series sum_(n=0)^(oo)r^(2n)

If the sum of the series Sigma_(n=0)^(oo) r^(n),|r|le 1 is s, then find the sum of the series Sigma_(n=0)^(oo) r^(2n),|r|le 1

Find the sum of the series sum_(r=1)^(n)r xx r!

Find the sum of the series (sum_(r=1)^(n) rxxr !)

Find the sum of the series sum_(r=1)^n rxxr !dot

Find the sum of the series (sum_(r=1)^(n) rxxr !)

Find the sum of the series sum_(r=1)^n rxxr !dot

Find the sum of the series sum_(r=1)^(n) r x^(r-1) using calculus .