Solve the following math problem efficiently and clearly:

- For simple problems (2 steps or fewer):
Provide a concise solution with minimal explanation.

- For complex problems (3 steps or more):
Use this step-by-step format:

## Step 1: [Concise description]
[Brief explanation and calculations]

## Step 2: [Concise description]
[Brief explanation and calculations]

...

Regardless of the approach, always conclude with:

Therefore, the final answer is: $oxed{answer}$. I hope it is correct.

Where [answer] is just the final number or expression that solves the problem.

Problem: Let $\mathbf{a},$ $\mathbf{b},$ $\mathbf{c}$ be unit vectors such that
\[\mathbf{a} \times (\mathbf{b} \times \mathbf{c}) = \frac{\mathbf{b} + \mathbf{c}}{\sqrt{2}},\]and such that $\{\mathbf{a}, \mathbf{b}, \mathbf{c}\}$ is a linearly independent set.

Find the angle between $\mathbf{a}$ and $\mathbf{b},$ in degrees.
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