# How can I find the component of this 3D tensor in a 2D space?

Good day Dear community,

I'm really new in this field, so I truly appreciate your help and advises. I have this math problem:

Consider the two mutually perpendicular unit vectors:

$$i_a=3/5 i_1-4/5 i_2$$

$$i_b=4/5 i_1+3/5 i_2$$

Also, I have this Tensor: $$[A]=\begin{bmatrix}-2&3&1\\4&2&3\\-2&1&0\end{bmatrix}$$

I need to find the component of the tensor $$A_{ab}$$

Thanks ind advance for any help!

• Since you only mention two unit vectors this suggests your underlying space has two dimensions - but your tensor components have three dimensions. Which is correct ? – gandalf61 Dec 6 at 15:34
• Yes, You're right. I'm going to modify the post. Thanks! – Leonardo H. Talero-Sarmiento Dec 6 at 15:37