Δ
(
m
1
→
v
1
+
m
2
→
v
2
)
=
0
Δ
(
m
1
v
→
1
+
m
2
v
→
2
)
=
0
Close
Log in
Books
Repository
eAnswer
ePortfolio
Close
Log in
Books
Repository
eAnswer
ePortfolio
Log in
New user
OK
Error
Forgot?
Log in
Register
Recover
OK
Error
Change