(
O
A
)
2
,
(
O
B
)
2
≈
0
(
O
A
)
2
,
(
O
B
)
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