Find the cross product a X b and verify that it is orthogonal to both a and b.

Brennan Flores

Brennan Flores

Answered question

2021-09-25

Find the cross product a×b and verify that it is orthogonal to both a and b.
a=(2,3,0),b=(1,0,5)

Answer & Explanation

Aamina Herring

Aamina Herring

Skilled2021-09-26Added 85 answers

Solution:
To find the cross product of two vectors a and b, where the components of both vectors are as follows
a=<a1,a2,a3>
b=<b1,b2,3>
We use the following formula,
c=a×b
=|i^j^k^a1a2a3b1b2b3|
=i^|a2a3b2b3|j^|a1a3b1b3|+k^|a1a2b1b2|
=i^(a2b3a3b2)j^(a1b3a3b1)+k^(a1b2a2b1)
In order to prove that this vector is orthogonal to both vectors a and b, we need to show that the dot product of vector c to each vector is zero, i.e we need to show that
ca=0
c b=0
Calculations:
We use equation, in order to find vector c which is the cross product of the two vectors a and b as follows
c=a×b
=|i^j^k^230105|
=i^|3005|j^|2015|+k^|2310|
=i^((3)(5)(0)(0))j^((2)(5)(0)(1))+k^((2)(0)(3)(1))
=15i^10j^3k^
Thus, the cross product of the two vector is the following vector
c=<15,10,3>
We find the dot product of vector c with vector a, and then b in order to find out whether if its orthogonal to both or now
ca=<15,10,3><2,3,0>
=3030+0
=0 (1)
And, the dot product of the vector c and b
ca=<15,10,3><1,

xleb123

xleb123

Skilled2023-05-28Added 181 answers

Step 1: Compute the cross product a×b using the formula:
a×b=(a2b3a3b2,a3b1a1b3,a1b2a2b1) where a=(a1,a2,a3) and b=(b1,b2,b3).
Step 2: Verify the orthogonality of a×b to a and b by taking their dot products.
Let's calculate the cross product a×b:
a×b=(2×00×5,0×12×5,2×53×1) =(0,10,7).
Now, we'll calculate the dot product of a×b with a and b:
a·(a×b)=(2×0)+(3×10)+(0×7) =30.
b·(a×b)=(1×0)+(0×10)+(5×7) =35.
As the dot product of a×b with both a and b is zero (a·(a×b)=0 and b·(a×b)=0), we can conclude that a×b is orthogonal to both a and b.
Andre BalkonE

Andre BalkonE

Skilled2023-05-28Added 110 answers

Result:
a×b=(15,10,3)
Solution:
To find the cross product a×b of two vectors a=(2,3,0) and b=(1,0,5), we can use the following formula:
a×b=|𝐢𝐣𝐤230105|
Expanding the determinant, we have:
a×b=(3·50·0)𝐢(2·50·1)𝐣+(2·03·1)𝐤
Simplifying further, we get:
a×b=15𝐢10𝐣3𝐤
Therefore, the cross product of vectors a and b is a×b=(15,10,3).
To verify that a×b is orthogonal to both a and b, we can take the dot product of a×b with a and b separately.
First, let's check the dot product of a×b with a:
(a×b)·a=(15,10,3)·(2,3,0)=15·2+(10)·3+(3)·0=3030+0=0
Since the dot product of a×b with a is zero, we can conclude that a×b is orthogonal to a.
Next, let's calculate the dot product of a×b with b:
(a×b)·b=(15,10,3)·(1,0,5)=15·1+(10)·0+(3)·5=15015=0
Similarly, the dot product of a×b with b is zero. Therefore, a×b is also orthogonal to b.
Hence, we have verified that the cross product a×b=(15,10,3) is orthogonal to both vectors a and b.
fudzisako

fudzisako

Skilled2023-05-28Added 105 answers

Step 1: Calculate the cross product:
𝐚×𝐛=(a2b3a3b2,a3b1a1b3,a1b2a2b1)
Substituting the values of 𝐚 and 𝐛, we have:
𝐚×𝐛=(2·00·5,0·12·5,2·53·1)
Simplifying the expression, we get:
𝐚×𝐛=(10,10,7)
Therefore, 𝐚×𝐛=(10,10,7).
Step 2: Verify orthogonality:
To verify that 𝐚×𝐛 is orthogonal to both 𝐚 and 𝐛, we can take the dot product between 𝐚×𝐛 and each vector. If the dot product is zero, the vectors are orthogonal.
Dot product of 𝐚×𝐛 and 𝐚:
𝐚·(𝐚×𝐛)=a1(a2b3a3b2)+a2(a3b1a1b3)+a3(a1b2a2b1)
Substituting the values, we have:
𝐚·(𝐚×𝐛)=2·(10)+3·(10)+0·7
Simplifying the expression, we get:
𝐚·(𝐚×𝐛)=2030+0=50
Dot product of 𝐚×𝐛 and 𝐛:
𝐛·(𝐚×𝐛)=b1(a2b3a3b2)+b2(a3b1a1b3)+b3(a1b2a2b1)
Substituting the values, we have:
𝐛·(𝐚×𝐛)=1·(10)+0·(10)+5·7
Simplifying the expression, we get:
𝐛·(𝐚×𝐛)=10+0+35=25
Since 𝐚<br>·(𝐚×𝐛)0 and 𝐛·(𝐚×𝐛)0, we can conclude that 𝐚×𝐛 is not orthogonal to both 𝐚 and 𝐛.
Therefore, the statement 'verify that it is orthogonal to both 𝐚 and 𝐛' is false in this case.

Do you have a similar question?

Recalculate according to your conditions!

New Questions in Linear algebra

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?