The next set of problems are about performing calculations with λ-functions.
The first one is to check that the reader is confident with mixing λ-calculus and algebraic operators:
Compute the value of (λx.x + 1) 3
Let's use β-reduction on this expression:
(λx.x + 1) 3 ⇒ 3 + 1 ⇒ 4