This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Complex exponentiation is nonzero if its base is nonzero. (Contributed by Mario Carneiro, 2-Aug-2014)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | cxpne0 | |- ( ( A e. CC /\ A =/= 0 /\ B e. CC ) -> ( A ^c B ) =/= 0 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | cxpef | |- ( ( A e. CC /\ A =/= 0 /\ B e. CC ) -> ( A ^c B ) = ( exp ` ( B x. ( log ` A ) ) ) ) |
|
| 2 | id | |- ( B e. CC -> B e. CC ) |
|
| 3 | logcl | |- ( ( A e. CC /\ A =/= 0 ) -> ( log ` A ) e. CC ) |
|
| 4 | mulcl | |- ( ( B e. CC /\ ( log ` A ) e. CC ) -> ( B x. ( log ` A ) ) e. CC ) |
|
| 5 | 2 3 4 | syl2anr | |- ( ( ( A e. CC /\ A =/= 0 ) /\ B e. CC ) -> ( B x. ( log ` A ) ) e. CC ) |
| 6 | 5 | 3impa | |- ( ( A e. CC /\ A =/= 0 /\ B e. CC ) -> ( B x. ( log ` A ) ) e. CC ) |
| 7 | efne0 | |- ( ( B x. ( log ` A ) ) e. CC -> ( exp ` ( B x. ( log ` A ) ) ) =/= 0 ) |
|
| 8 | 6 7 | syl | |- ( ( A e. CC /\ A =/= 0 /\ B e. CC ) -> ( exp ` ( B x. ( log ` A ) ) ) =/= 0 ) |
| 9 | 1 8 | eqnetrd | |- ( ( A e. CC /\ A =/= 0 /\ B e. CC ) -> ( A ^c B ) =/= 0 ) |