That is indeed the right answer, for
n=4, you have eight nodal points if you think of it conceptually,
when as in a regular sin or cos function,
the period is divided by four causing the graph to split into
eight cycles. -> return to
the questions page
Congratulations 
as in a regular sin or cos function,
the period is divided by four causing the graph to split into
eight cycles. -> return to
the questions page