When weight is an engineering design constraint, sometimes a composite material is employed. In order to strengthen the material, it is layered on at different angles to reduce the amount of stress that it experiences. This is particularly important to aerospace designs as mass reduction is common practice. One example of using a composite material is carbon fiber which is used on corvette bodies and another is Kevlar for bullet proof vests. To solve the problem, it is plugged into a reduced compliance matrix where m = cos($ \theta$) and n = sin($ \theta$) as seen below. The strains are then entered into a vector. Using matlab, this operation can be simplified to a simple Ax=B problem.
Figure 4: Compliance Matrix
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