Metamath Proof Explorer


Theorem cxpmuld

Description: Product of exponents law for complex exponentiation. Proposition 10-4.2(b) of Gleason p. 135. (Contributed by Mario Carneiro, 30-May-2016)

Ref Expression
Hypotheses rpcxpcld.1
|- ( ph -> A e. RR+ )
rpcxpcld.2
|- ( ph -> B e. RR )
cxpmuld.4
|- ( ph -> C e. CC )
Assertion cxpmuld
|- ( ph -> ( A ^c ( B x. C ) ) = ( ( A ^c B ) ^c C ) )

Proof

Step Hyp Ref Expression
1 rpcxpcld.1
 |-  ( ph -> A e. RR+ )
2 rpcxpcld.2
 |-  ( ph -> B e. RR )
3 cxpmuld.4
 |-  ( ph -> C e. CC )
4 cxpmul
 |-  ( ( A e. RR+ /\ B e. RR /\ C e. CC ) -> ( A ^c ( B x. C ) ) = ( ( A ^c B ) ^c C ) )
5 1 2 3 4 syl3anc
 |-  ( ph -> ( A ^c ( B x. C ) ) = ( ( A ^c B ) ^c C ) )