Write a boolean expression that is true if and only if x is

Write a boolean expression that is true if and only if x is true and y is false

Write a boolean expression that is true if and only if i is at least 20

Write a boolean expression that is true if and only if i is smaller than 10 and z is true

Solution

1) x ^ ~y (x and not y)

2) i >= 20 (Here, >= satisfies at least 20 condition)

3) i < 10 && z (when z is true, and i is less than 10)