Given vector a =(4.3), vector B =(2,4) then cos =?

Given vector a =(4.3), vector B =(2,4) then cos =?

Cosine value = Vector inner product / Vector modular product =(4*2+3*4)/[ Srt (42+32)* Srt (22+42)]=2/ Srt5
(Sprt is the programming language, meaning square root)

What is the formula for the distance between two parallel planes in a vector?

A square + B square + C square | D1- D2| under the root sign. Note that the coefficients of the two planes must be the same to use this formula.

A square + B square + C square | D1-D2| under the root sign. Note that the coefficients of the two planes must be consistent to use this formula.

0

This is good to remember. Let two vector coordinates be (x1, y1, z1),(x2, y2, z2)(none of them are zero vectors).
1 Vertical is point multiplication to 0, just remember the definition of point multiplication: each coordinate component is multiplied and added. So the vertical formula is x1x2+y1y2+z1z2=0
2 Parallel is better to remember, that is, the corresponding coordinate components are proportional, x1: x2=y1: y2=z1: z2

Vector parallel, vertical formula

The two vectors a, b are parallel: a=λb (b is not a zero vector); the two vectors are vertical: the quantity product is 0, i.e. a•b=0
Coordinate representation: a=(x1, y1), b=(x2, y2)
A//b if and only if x1y2-x2y1=0
A⊥b if and only if x1x2+y1y2=0

Two vectors a, b b are parallel: a=λb (b is not a zero vector); the two vectors are vertical: the quantity product is 0, i.e. a•b=0
Coordinate representation: a=(x1, y1), b=(x2, y2)
A//b if and only if x1y2-x2y1=0
A⊥b if and only if x1x2+y1y2=0

If vector a=(3,-m) and vector B=(-2,1) are perpendicular, then M=how many? Find the formula to find the tutorial? If vector a =(3,-m) and vector B =(-2,1) are perpendicular, then M = how many? Find the formula for the tutorial?

Vector a is perpendicular to vector b
3×(-2)+(-M)×1=0
M=-6
PS: vector a=(x, y) is perpendicular to b=(m, n), then xm+yn=0

What conditions do vectors A and B satisfy so that a+b and a-b are perpendicular to each other

Parallel