Theorem pow12 | index | src |

theorem pow12 (a: nat): $ a ^ 1 = a $;
StepHypRefExpression
1 eqtr
a ^ 1 = a * a ^ 0 -> a * a ^ 0 = a -> a ^ 1 = a
2 powS
a ^ suc 0 = a * a ^ 0
3 2 conv d1
a ^ 1 = a * a ^ 0
4 1, 3 ax_mp
a * a ^ 0 = a -> a ^ 1 = a
5 eqtr
a * a ^ 0 = a * 1 -> a * 1 = a -> a * a ^ 0 = a
6 muleq2
a ^ 0 = 1 -> a * a ^ 0 = a * 1
7 pow0
a ^ 0 = 1
8 6, 7 ax_mp
a * a ^ 0 = a * 1
9 5, 8 ax_mp
a * 1 = a -> a * a ^ 0 = a
10 mul12
a * 1 = a
11 9, 10 ax_mp
a * a ^ 0 = a
12 4, 11 ax_mp
a ^ 1 = a

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp, itru), axs_pred_calc (ax_gen, ax_4, ax_5, ax_6, ax_7, ax_10, ax_11, ax_12), axs_set (elab, ax_8), axs_the (theid, the0), axs_peano (peano1, peano2, peano5, addeq, muleq, add0, addS, mul0, mulS)