Q. For all positive integral values of $n,\ 3^{2n} - 2n + 1$ is divisible by
A) 2
B) 4
C) 8
D) 12
Explanation
(a)
On putting $n = 2$ in $3^{2n} - 2n + 1$, we get
$3^{2 \times 2} - 2 \times 2 + 1 = 81 - 4 + 1 = 78$
Which is divisible by 2
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.