No this has nothing to do with Galileo's Law it is a completely different

motion problem.

What stays the same is the definition of average velocity it is still

[s(t2) - s(t1)]/(t2-t1)

s= 5sin(πt) + 2cos(πt

Compute [s(2) -s(1)]/[2-1]

The instantaneous velocity is the derivative but as you've been asked for

an approximation I'm assuming you haven't done derivatives yet?

Compute [s(1.01) -s(1)]/[1.01-1]