From 5b7eafd0f00a16d78f99a27f5c7d5a0de77dc7e6 Mon Sep 17 00:00:00 2001 From: Stephane Glondu Date: Wed, 21 Jul 2010 09:46:51 +0200 Subject: Imported Upstream snapshot 8.3~beta0+13298 --- theories/Numbers/Natural/Abstract/NMul.v | 87 -------------------------------- 1 file changed, 87 deletions(-) delete mode 100644 theories/Numbers/Natural/Abstract/NMul.v (limited to 'theories/Numbers/Natural/Abstract/NMul.v') diff --git a/theories/Numbers/Natural/Abstract/NMul.v b/theories/Numbers/Natural/Abstract/NMul.v deleted file mode 100644 index 0b00f689..00000000 --- a/theories/Numbers/Natural/Abstract/NMul.v +++ /dev/null @@ -1,87 +0,0 @@ -(************************************************************************) -(* v * The Coq Proof Assistant / The Coq Development Team *) -(* forall m1 m2 : N, m1 == m2 -> n1 * m1 == n2 * m2. -Proof NZmul_wd. - -Theorem mul_0_l : forall n : N, 0 * n == 0. -Proof NZmul_0_l. - -Theorem mul_succ_l : forall n m : N, (S n) * m == n * m + m. -Proof NZmul_succ_l. - -(** Theorems that are valid for both natural numbers and integers *) - -Theorem mul_0_r : forall n, n * 0 == 0. -Proof NZmul_0_r. - -Theorem mul_succ_r : forall n m, n * (S m) == n * m + n. -Proof NZmul_succ_r. - -Theorem mul_comm : forall n m : N, n * m == m * n. -Proof NZmul_comm. - -Theorem mul_add_distr_r : forall n m p : N, (n + m) * p == n * p + m * p. -Proof NZmul_add_distr_r. - -Theorem mul_add_distr_l : forall n m p : N, n * (m + p) == n * m + n * p. -Proof NZmul_add_distr_l. - -Theorem mul_assoc : forall n m p : N, n * (m * p) == (n * m) * p. -Proof NZmul_assoc. - -Theorem mul_1_l : forall n : N, 1 * n == n. -Proof NZmul_1_l. - -Theorem mul_1_r : forall n : N, n * 1 == n. -Proof NZmul_1_r. - -(* Theorems that cannot be proved in NZMul *) - -(* In proving the correctness of the definition of multiplication on -integers constructed from pairs of natural numbers, we'll need the -following fact about natural numbers: - -a * n + u == a * m + v -> n + m' == n' + m -> a * n' + u = a * m' + v - -Here n + m' == n' + m expresses equality of integers (n, m) and (n', m'), -since a pair (a, b) of natural numbers represents the integer a - b. On -integers, the formula above could be proved by moving a * m to the left, -factoring out a and replacing n - m by n' - m'. However, the formula is -required in the process of constructing integers, so it has to be proved -for natural numbers, where terms cannot be moved from one side of an -equation to the other. The proof uses the cancellation laws add_cancel_l -and add_cancel_r. *) - -Theorem add_mul_repl_pair : forall a n m n' m' u v : N, - a * n + u == a * m + v -> n + m' == n' + m -> a * n' + u == a * m' + v. -Proof. -intros a n m n' m' u v H1 H2. -apply (@NZmul_wd a a) in H2; [| reflexivity]. -do 2 rewrite mul_add_distr_l in H2. symmetry in H2. -pose proof (NZadd_wd _ _ H1 _ _ H2) as H3. -rewrite (add_shuffle1 (a * m)), (add_comm (a * m) (a * n)) in H3. -do 2 rewrite <- add_assoc in H3. apply -> add_cancel_l in H3. -rewrite (add_assoc u), (add_comm (a * m)) in H3. -apply -> add_cancel_r in H3. -now rewrite (add_comm (a * n') u), (add_comm (a * m') v). -Qed. - -End NMulPropFunct. - -- cgit v1.2.3