Description: Exponent subtraction law for complex exponentiation. (Contributed by Mario Carneiro, 22-Sep-2014)
Ref | Expression | ||
---|---|---|---|
Assertion | cxpsub | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | negcl | |
|
2 | cxpadd | |
|
3 | 1 2 | syl3an3 | |
4 | simp2 | |
|
5 | simp3 | |
|
6 | 4 5 | negsubd | |
7 | 6 | oveq2d | |
8 | simp1l | |
|
9 | simp1r | |
|
10 | cxpneg | |
|
11 | 8 9 5 10 | syl3anc | |
12 | 11 | oveq2d | |
13 | cxpcl | |
|
14 | 8 4 13 | syl2anc | |
15 | cxpcl | |
|
16 | 8 5 15 | syl2anc | |
17 | cxpne0 | |
|
18 | 8 9 5 17 | syl3anc | |
19 | 14 16 18 | divrecd | |
20 | 12 19 | eqtr4d | |
21 | 3 7 20 | 3eqtr3d | |