Proceed $asin$ Example $3to$ rewrite each power series $as$ a power series whose general term involves

$xk.$

$n=1$

$ncnxn-1$

$=$

$+$

$k=2$

$xk$

$7$

$n=0$

$cnxn+2$

$=$

$k=2$

$xk$

Rewrite the given expression using a single power series whose general term involves

$xk.$

$n=1$

$ncnxn-1+7$

$n=0$

$cnxn+2$

$+$

$k=2$

Rewrite the given expression using a single power series whose general term involves $x^k.$