Chapter 5.8, Problem 10ES

In each of 8-10: (a) suppose a sequence of the form $1,t,t^2,t^3,\mathrm{...},t^n\mathrm{....}$ where $t\ne 0,$ satisfies the given recurrence relation (but not necessarily the initial conditions), and find all possible values of t: (b) suppose a sequence satisfies the given initial conditions as well as the recurrence relation, and find an explicit formula for the sequence.
10. $c_k=c_{k-1}+6c_{k-2},$ for every integer $k\ge 2$
   $c_0=0,c{1}_{}=3$