The range of $f(x)={ }^{7-x} P_{, b-3}$ is

Question

Professor PC Thomas Classes · Answer

$0 \leq x-3 \leq 7-x \Rightarrow 3 \leq x \leq 5$
$f(3)={ }^4 P_0=1 \mathrm{f}(4)={ }^3 P_1=3 f(5)={ }^2 P_2=2$