n - 5
n - 3
2n - 1
2n - 3
Correct answer is D
nP3nC2+nP0
nP3nC2=n!(n−3)!÷n!(n−2)!2!
n!(n−3)!×(n−2)(n−3)!2!n!=2n−4
nP0=n!(n−0)!=1
nP3nC2+nP0=2n−4+1=2n−3
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