Theorem nftru 1442

Description: The true constant has no free variables. (This can also be proven in one step with nfv 1508, but this proof does not use ax-17 1506.) (Contributed by Mario Carneiro, 6-Oct-2016.)

Assertion

Ref	Expression
nftru	|- F/ x T.

Proof of Theorem nftru

Step	Hyp	Ref	Expression
1		tru 1335	. 2 |- T.
2	1	nfth 1440	1 |- F/ x T.

Syntax hints:   T. wtru 1332   F/wnf 1436

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-gen 1425

This theorem depends on definitions:  df-bi 116  df-tru 1334  df-nf 1437

This theorem is referenced by:  nfmo  2017  dvelimc  2300  nfralxy  2469  nfrexxy  2470  nfralya  2471  nfrexya  2472  nfreuxy  2603  nfsbc  2924  nfcsb  3032  nfiotaw  5087  nfriota  5732  nfixpxy  6604