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All About Types of Multiplication of Vectors

A vector multiplication operation includes the scalar product and cross product, both of which are fundamental approaches in vector operations.

A vector multiplication operation includes the scalar product and cross product, both of which are fundamental approaches in vector operations.

The two types of vector multiplication will be discussed in detail in this article, as well as the differences between them. Have your notes on the following topics close at hand because we may need to refer to them while learning about vector multiplication, so make sure to keep them handy.

What is the best way to multiply vectors?

It’s critical to decide whether you want a scalar or a vector quantity when multiplying two or more vectors because the result will be different. The strategy we’ll need to use will be determined by our response to that question..

In vector multiplication, there are three possible products: the vector multiplied by a scalar factor, the dot (or scalar) product, and the cross (or vector) product. Vector multiplication is a mathematical operation that involves multiplying two vectors by a scalar factor.

  • At this point, we should have learnt about distributing scalar components to a vector, which is the first process we’ll go over in this section. 
  • As you might have suspected, the dot product, also known as the scalar product, yields a single scalar quantity.
  • Similar to the foreach, the cross product yields a vector quantity.

Our explanation will be limited to the last two strategies, which are dot products and cross products. Because their operators depict a dot (.) and a cross symbol (x), these names will assist you in identifying the operation that has to be performed.

Vector multiplication rules

The two goods will produce distinct results and go through different processes. This is why it is important to understand what the dot and cross products are representing in the equation.

The Dot Product and Its Rules

The dot product is a mathematical expression that represents the projection of one vector onto another vector. Consider the case where we have and, where the dot product of and is just the projection of onto the vector of interest.

Take a look at this illustration to see what occurs when we find the dot product of and and What happens is that we take the vector component of A along the direction of B and multiply it by the magnitude of the vector component B 

A.B= (Acos θ)B=ABcos θ

As a result, the dot product of A and B (A.B) is just the product of the magnitudes of the two vectors multiplied by the cosine of the angle between them.

Properties of dot product

Because the final product is a scalar number, the dot product is often referred to as the scalar number. The following are some significant properties of the scalar product to bear in mind when using it:

  • The scalar product is commutative in the following way:

A.B=B.A

  • The scalar product has the distributive property:

A.(B+C)=B.(A+C)

  • When you take the scalar product of two perpendicular vectors, the result will always be equal to 0(since cos 90° is equal to 0).

Another method of calculating the dot product of the two vectors is to multiply their respective Cartesian components by one another. Assuming that,, and are the unit vectors along the,, and axes, respectively, we can calculate the product of A and B as illustrated  below.

A=A1i +A2j+A2k

B=B1i+ B2j +B3k

A.B= A1B1+A2B2+A3B3

The Cross-Product and Its Rules

A pattern may already be emerging here: for cross products, we employ the operator x, and the resulting product is a vector. As a result, the cross product or vector product requires us to take the direction into consideration.

A great approach to see the cross product of two vectors is to calculate the area of a parallelogram by multiplying the vectors together.

The cross product of A and B is equal to the product of Asin θ and B, as we can see from this.

AxB =(Asin θ)B=ABsin θn

Keep in mind that the unit vector n is just the vector that is perpendicular to both the and the This means that if we have two vectors and an angle between them, we can find the cross product by multiplying the magnitudes of the two vectors, which is the cross product. The result can then be multiplied by the sine of the angle formed by the two vectors in question.

Properties of cross product

Here are some of the most essential characteristics of vector or cross products that you should be aware of:

  • Vector or cross products are anti-commutative in the following ways:

A x B= -B x A

  • The vector product has a distributive advantage over the addition:

Ax(B+C) = AxB +AxC

  • The cross product of two parallel vectors will always equal 0.

Conclusion

A vector multiplication operation includes the scalar product and cross product, both of which are fundamental approaches in vector operations.In vector multiplication, there are three possible products: the vector multiplied by a scalar factor, the dot (or scalar) product, and the cross (or vector) product. Vector multiplication is a mathematical operation that involves multiplying two vectors by a scalar factor.The dot product is a mathematical expression that represents the projection of one vector onto another vector.When you take the scalar product of two perpendicular vectors, the result will always be equal to 0(since cos 90° is equal to 0).A pattern may already be emerging here: for cross products, we employ the operator x, and the resulting product is a vector. As a result, the cross product or vector product requires us to take the direction into consideration.The cross product of two parallel vectors will always equal to 0.

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