The math of cross-product and standard deviation

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Scalar and vectors are two important terms in physics. Scalar is a quantity that requires magnitude only whereas a vector needs magnitude plus direction for its representation. There are a set of procedures, calculations, and properties associated with it and called vector algebra which includes multiplication.
Vectors are different from numbers. The complexity lies in the information regarding paths, quantities, and angles which are explained in algebra. Hence vector algebra used two kinds of multiplication. I.e. dot product and cross product. Cross product is used to define vector quantities.
What is the cross product?
The cross product of the two vectors (a, b) results in the formation of a third vector which is at the right angle of the parent vectors. Calculation of a cross product is a binary process on two vectors in a three-dimensional space.
The resultant vector is present at the angle of 90 degrees in a 3D plane. A three-dimensional plane consists of three independent directions. The directions are elevation, extensiveness, and deepness.
Calculation of cross product
Cross product can be calculated by this formula:
c=ab=|a||b|sinθn
Here "a" represents the magnitude of vector A, and “b” represents the magnitude of vector B. θ is the angle between them. The initial or parent vectors produced a new vector called “C”. 

The above expression of the cross product throws light on a significant point. i.e “direction of the vectors”. It is noted that the vectors “a” and “b” must be collinear and do not lie in the same direction. If the vectors “a” and “b” will lie parallel to each other then the angle formed between them will be zero. Hence both vectors will cancel each other's effect and provide unfavorable results.
Calculation of cross-product in three dimensional space:
Calculation of a scalar product strict to two planes only. i.e x and y. But the calculation of a cross product might get complicated in a three-dimensional space as it involves finding unit vectors and direction. A new formula is used for this calculation; it works on the division of three-dimensional space into three constituents. Hence it makes it easy to solve the problem. The designed path is associated with a path in space and a number which implies the length of the object. The three dimensions x, y, and z are denoted by i, j, and k in this unitary representation.
How to find the direction of vectors?
A specific rule is designed to find the direction of vectors called a right-hand rule. In this rule, two fingers are inclined straight in a path whereas the thumb lies in an upward direction. From which the fingers represent the magnitude of the vectors. 

Whereas the erected thumb shows the direction of the new vector.
Cross product is a very specific calculation used in physics. This algebraic calculation could be made easier by concepts and practice. After understanding the core points of the term, you can minimize your effort by calculating the cross product from cross product calculator

You just need to put the value of parent vectors and it will show you the value of the resultant vector. You will save your time and get accurate results.
What is the standard deviation?
It is a specific quantity used in statistics to express the deviation of numbers in a group from the mean value of the group. It is neither calculated from median or mode but it is calculated from the arithmetic to mean only. Standard deviation is shown by the symbol Sigma (σ).
How to calculate the standard deviation?
Standard deviation in a population can be calculated from this formula.


Here x represents the value In a data set, µ is the mean of given data and n shows the total number of items.
This formula is applicable for calculating in a population
whereas the standard deviation in a sample data can be calculated like:

First, find the mean of the given data. After getting the mean value subtract it from each value in the set. The resultant will be called deviation. Take the square root of each deviation and find out the summation of taken squares. Then divide it by the total number. The resultant will be called variance. Lastly, take the square root of the variance and you will get the standard deviation. 

If this procedure seems difficult and you have plenty of work to do. You can also use a standard deviation calculator. It will reduce the pressure of learning formulas and derive results in milliseconds.

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