Can anyone PLEASE explain axis rotation?

AI Thread Summary
Axis rotation involves using a rotation matrix to transform coordinates in three-dimensional space. For a 45-degree rotation about the y-axis, the matrix is derived from trigonometric functions, specifically cosine and sine of the angle. The resulting matrix is structured to maintain the y-coordinate while adjusting the x and z coordinates based on the rotation. Understanding the derivation of this matrix clarifies how points in 3D space are affected by rotation. The provided link offers further insights into the theory behind these transformations.
m0nk3y
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So I am asked to rotate by 45 degrees about the y-axis.

With the power of the net i found that it is;
[ cos(45) 0 sin (45);
0 1 0;
-sin(45) 0 cos(45)]

i really would like to understand HOW they get this.

THANKS in advance!
 
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Thank you, that helped alot! I get finally get it now!
 

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