Expanding:

`f(t)=` `t^2 · u(t)` `-t^2 · u(t-2)` ` + 4 · u(t-2)`

`f(t)=` `t^2 · {u(t)` ` - u(t-2)}` ` + 4 · u(t-2)`

So our graph is as follows. It is a parabola before `t=2`, and then has constant value `4` thereafter.

Graph of `f(t)`.

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