Math Help - Probability question involving recurrence relations

1. Probability question involving recurrence relations

Can anyone help with part (a)ii, is pk=(1/2)^k? I can't see how to find qk

2. Hello,

If you manage to show the recurrence relation for $q_k$, you can then find the formula for q_k.
Then just notice that q_1=p_1.

And yes, p_k=(1/2)^k

3. that's good to know about pk, but how would you go about deriving the expression for qk? I've tried using partition theorem of many different partitions, such as first step = stay, first step = move

4. solved!