Nuprl - Pf is member append disjunction lemma 1 2

(18steps) PrintForm Definitions list 3 jlc Sections Support(jlc) Doc

At: is member append disjunction lemma 1 2

1. T: Type
2. eq: {T}
3. x: T
4. L: T List
5. M: T List
6. x(eq) L x(eq) M

x(eq) (L @ M)

By: ListInd 4 THEN Reduce 0

Generated subgoals:

1 False x(eq) M x(eq) M

2 6. u: T
7. v: T List
8. x(eq) v x(eq) M x(eq) (v @ M)
if eq(x,u) true else x(eq) v fi x(eq) M if eq(x,u) true else x(eq) (v @ M) fi

About:

(18steps) PrintForm Definitions list 3 jlc Sections Support(jlc) Doc

1	`False x(eq) M x(eq) M`
2	6. `u:` `T` 7. `v:` `T List` 8. `x(eq) v x(eq) M x(eq) (v @ M)` `if eq(x,u) true else x(eq) v fi x(eq) M if eq(x,u) true else x(eq) (v @ M) fi`