(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Question: The strain state in a point is defined by the tensor:

0.9 0 0

0 -0.4 0.2

0 0.2 0.6

- Define principal strains and directions in the point

- Explain how deforms the element shown in figure 2b (they just drew a cube on 3d axis)

- Draw the principal directions

2. Relevant equations

So i know that ε^3 - I1ε^2 - I2ε - I3 = 0

3. The attempt at a solution

and for the I values, i subbed the tensor values in and got I1 = 0.7, I2 = 0.02, I3 = -0.252

I have a feeling i'm subbing the wrong values though. is εx = εxx from the tensor above?

Becuase the end equation i get, does not give me any roots.

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# Homework Help: Defining principal strain + direction

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