Q. If $n$ is a positive integer, then $5^{2n + 2} - 24n - 25$ isdivisible by

A) 574
B) 575
C) 675
D) 576
Explanation

(d)
Let $P(n) = 5^{2n + 2} - 24n - 25$
For $\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ n = 1$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ P(1) = 5^{4} - 24 - 25 = 576$
$\ \ \ \ \ \ \ \ \ \ P(2) = 5^{6} - 24(2) - 25 = 15552$
$\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ = 576 \times 27$
Here, we see that $P(n)$ is divisible by 576

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.