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Question
Let \[f : \left[ - \frac{\pi}{2}, \frac{\pi}{2} \right] \to\] A be defined by f(x) = sin x. If f is a bijection, write set A.
Solution
\[\because\] f is a bijection,
co -domain of f = range of f
As \[- 1 \leq \sin x \leq 1\]
\[- 1 \leq y \leq 1\]
So, A = [-1 , 1]
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