Let $S$ be the set of points with polar coordinates $(r, \theta),$ where $1 \le r \le 2$ and $0 \le \theta \le \frac{\pi}{2}.$  Compute the area of $S.$
Question:
Let $S$ be the set of points with polar coordinates $(r, \theta),$ where $1 \le r \le 2$ and $0 \le \theta \le \frac{\pi}{2}.$  Compute the area of $S.$
Answer:
Let's think step by step.

user
\frac{3 \pi}{4}
Let $S$ be the set of points with polar coordinates $(r, \theta),$ where $1 \le r \le 2$ and $0 \le \theta \le \frac{\pi}{2}.$  Compute the area of $S.$
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