Try these problems to practice some "proof bits". If you get jammed, try clicking on the "tips".

Note: I will be using ">" to represent the horseshoe, "@" to represent the tiplebar, and "//" to represent the conclusion. There is more than one way of correctly proving these conclusions.

PROBLEM 1
1) T > (A • W)
2) W > X
3) ~(X v U) // ~T
tip

PROBLEM 2
1) ~A
2) ~(A v Z) > W
3) ~Z v ~X
4) X // R > W
tip

PROBLEM 3
1) (A > T) > R
2) ~(R • Q)
3) T • W // ~Q
tip

PROBLEM 4
1) ~(B > M) @ T
2) B
3) ~(M v W) // T
tip

PROBLEM 5
1) (A > B) v E
2) W > A
3) ~(~W v B) // R > E
tip

PROBLEM 6
1) M > (A • S)
2) ~(T v S) > R
3) ~(S v M)
4) K @ T
5) ~K // ~M • R
tip

PROBLEM 7
1) (T > W) > Y
2) W
3) ~(A • B) > Z
4) ~A // Y @ Z
tip

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