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Q.
The function $f_4$ defined by
Relations and Functions - Part 2
Solution:
Since, distinct elements of $X_1$ have distinct images in $X_4$ and every element in $X_4$ has a unique pre image in $X_1$.
$\therefore $ The function $f_4$ is both one-one and onto.
$\rightarrow f_4$ is bijective.
