SAGAR SINGH - IIT DELHI
Last Activity: 14 Years ago
Dear nishant,
1) If
then magnitude or length or norm or absolute value of
is 
2) A vector of unit magnitude is unit vector. If
is a vector then unit vector of
is denoted by
and

3) Important unit vectors are
, where
,
, 
4) The components of unit vectors of
are called the direction cosines of
, denoted by
and 
5) If
,
,
, then
are called directional angles of the vectors
and 
6) If
and
are the two points, then 
7) If
and
then


8) If
and
is a scalar number, then
.
9) In vector addition
I. 
II. 
III. 
IV.
,
is the additive identity in vector addition.
V.
,
is the inverse in vector addition.
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Sagar Singh
B.Tech IIT Delhi