44 lines
660 B
Text
44 lines
660 B
Text
-- BEGINWAIT
|
||
-- ENDWAIT
|
||
-- BEGINWAIT
|
||
-- ENDWAIT
|
||
-- BEGININFO
|
||
-- TYPE|4|13
|
||
Type₁
|
||
-- ACK
|
||
-- TYPE|4|16
|
||
Prop
|
||
-- ACK
|
||
-- IDENTIFIER|4|16
|
||
true
|
||
-- ACK
|
||
-- ENDINFO
|
||
-- BEGINWAIT
|
||
-- ENDWAIT
|
||
-- BEGININFO
|
||
-- TYPE|4|13
|
||
Type₁
|
||
-- ACK
|
||
-- TYPE|4|16
|
||
Prop
|
||
-- ACK
|
||
-- IDENTIFIER|4|16
|
||
true
|
||
-- ACK
|
||
-- ENDINFO
|
||
-- BEGINFINDG
|
||
add.assoc|∀ (n m k : ℕ), n + m + k = n + (m + k)
|
||
-- ENDFINDG
|
||
-- BEGINWAIT
|
||
-- ENDWAIT
|
||
-- BEGINSHOW
|
||
import logic data.nat.basic
|
||
open nat eq.ops
|
||
|
||
definition a := true
|
||
|
||
theorem tst (a b c : nat) : a + b + c = a + c + b :=
|
||
calc a + b + c = a + (b + c) : _
|
||
... = a + (c + b) : {!add.comm}
|
||
... = a + c + b : (!add.assoc)⁻¹
|
||
-- ENDSHOW
|