Find 2 Unit Vectors at 60 Degrees with <3,4> - Dot Product Calculation

In summary, the conversation is about finding 2 unit vectors that make a 60 degree angle with the vector <3,4>. The summary also mentions the use of the cosine function and the need to find a and b values that satisfy the unit vector requirement.
  • #1
nameVoid
241
0
Find 2 unit vectors that make a 60 degree angle with <3,4>

Vector <a,b>
Taking b=1 cos60=1/2

3a+4=(5/2 )sqrt(a^2+1)

36a^2+96a+64=25a^2+25
11a^2+96a=-39
(sqrt(11)a+48)^2= 2265
+- a=(sqrt(2265)-48)/sqrt(11)
 
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  • #2
nameVoid said:
Find 2 unit vectors that make a 60 degree angle with <3,4>

Vector <a,b>
Taking b=1 cos60=1/2

3a+4=(5/2 )sqrt(a^2+1)

36a^2+96a+64=25a^2+25
11a^2+96a=-39
(sqrt(11)a+48)^2= 2265
+- a=(sqrt(2265)-48)/sqrt(11)

I don't see a question here.

But let me preempt it with a question of my own. You're asked to find unit vectors. Can you think of another condition you can impose on a and b to meet this requirement?

It's fine to do it the way you did (letting b = 1), but then you still have to find unit vectors in those directions. More work.
 

What is a unit vector?

A unit vector is a vector with a magnitude of 1. It is often used to describe direction without considering the length of the vector.

How do you find unit vectors?

To find a unit vector, divide a given vector by its magnitude. This will result in a vector with a magnitude of 1 and the same direction as the original vector.

What is the dot product?

The dot product is a mathematical operation that takes two vectors and produces a scalar quantity. It is calculated by multiplying the magnitudes of the two vectors and the cosine of the angle between them.

How do you calculate the dot product?

To calculate the dot product of two vectors, multiply their corresponding components and then add the products together.

How do you find two unit vectors at 60 degrees?

To find two unit vectors at 60 degrees, you can use the formula cos(60) = u * v / |u||v|, where u and v are the given vectors. Solve for u or v by dividing by the magnitude and then normalizing the vector to get a unit vector.

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