function

5 (t-2)²  - 4 (t-2)  +3        expand, collect 'like' terms and simplify.....

If g(t)=5t^2-4t+3 then g(t-2) would be 5(t-2)^2-4(t-2)+3

5(t-2)^2-4(t-2)+3

=5(t^2-4t+4)-4t+8+3

=5t^2-20t+20-4t+11

=5t^2-24t+31 is our final answer.