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N +1 n-dimensional vector, composed of vector group dimension linear (? ) Vector Group N +1 n-dimensional vector, the vector group composed of linear (? ) Vector Group
N +1 n-dimensional vector, consisting of a set of linear (correlated) vector sets
Because R≤n < n+1
So it's linear.
Mathematical Vector Judgment Vector a runs parallel to vector b, vector b is parallel to vector c, then vector a runs parallel to vector c
Wrong.
Counterexample: a and c are two intersecting vectors, b is zero vector
Two judgments about space vectors! 1. Move all the unit vectors in space to the same point as the starting point, and their end points form a circle. 2. The space vector is a directed line segment in space. Two judgments about space vectors! 1. Move all the unit vectors in the space to the same point as the starting point, and their ends form a circle. 2. The space vector is a directed line segment in space.
It's the ball, not the circle.
Yeah. Yeah.
A Simple Vector Judgment Problem What is the difference between the modulus of vector AB and that of vector BA? A Simple Vector Judgment Problem What is the difference between the modulus of vector AB and the modulus of vector BA?
Is equal
When the vector becomes "modulo ", the direction is not considered, only the length
Therefore,|AB|=|BA|
Module is length, is the length of vector, is scalar, i.e. no direction
So equal
Is equal
When the vector becomes "modulo ", the direction is not considered, only the length
Therefore,|AB|=|BA|
Module is length, is the length of the vector, is a scalar, i.e. no direction
So equal
The vectors a and b have an angle of 60 degrees, the modulus of b =6, and (a+2b)*(a-3b)=-176 Find the module of a
(A+2b)*(a-3b)=a^2-6b^2-a*b*cos60°=a^2-3a-216=-176
A =8
As shown in the figure, in Rt△ABC,∠C=90°, the lengths of AB, BC and CA are c, a and b respectively.
Let r.
S△ABC=1
2Ab=1
2(A+b+c)•r,
R=ab
A+b+c.
RELATED INFORMATIONS
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