题目
| ⊗ | a | b | c | d |
| a | a | a | a | a |
| b | a | b | c | d |
| c | a | c | c | a |
| d | a | d | a | d |
| ⊕ | a | b | c | d |
| a | a | b | c | d |
| b | b | b | b | b |
| c | c | b | c | b |
| d | d | b | b | d |
答案
所以d⊗(a⊕c)=d⊗c,
根据所给第一表格,得d⊗(a⊕c)=d⊗c=a,
故答案为:a.
| ⊗ | a | b | c | d |
| a | a | a | a | a |
| b | a | b | c | d |
| c | a | c | c | a |
| d | a | d | a | d |
| ⊕ | a | b | c | d |
| a | a | b | c | d |
| b | b | b | b | b |
| c | c | b | c | b |
| d | d | b | b | d |