複選題
17 若 ，則下列何者正確？
(A)  B)∇×(∇f ) = 0
(C)∇ • (∇ × (∇f )) = 0
(D)∇(∇ • (∇f )) = 0

答案：登入後查看
統計： A(0), B(5), C(5), D(0), E(0) #1021954