HP 48gII - Manual (Page 286)

Page 9-11
Magnitude
The magnitude of a vector, as discussed earlier, can be found with function
ABS. This function is also available from the keyboard (
„Ê). Examples
of application of function ABS were shown above.
Dot product
Function DOT is used to calculate the dot product of two vectors of the same
length. Some examples of application of function DOT, using the vectors A,
u2, u3, v2, and v3, stored earlier, are shown next in ALG mode. Attempts to
calculate the dot product of two vectors of different length produce an error
message:
Cross product
Function CROSS is used to calculate the cross product of two 2-D vectors, of
two 3-D vectors, or of one 2-D and one 3-D vector. For the purpose of
calculating a cross product, a 2-D vector of the form [A
x
, A
y
], is treated as the
3-D vector [A
x
, A
y
,0]. Examples in ALG mode are shown next for two 2-D and
two 3-D vectors. Notice that the cross product of two 2-D vectors will produce
a vector in the z-direction only, i.e., a vector of the form [0, 0, C
z
]: