If f(x)=5 - 2x and f(3k)= f(k+1), then f(k) = ?

A 0.5

B 1

C 4

D 8

E None

Correct Answer: Option C

Solution:

দেয়া আছে, f(x) = 5 - 2x

=> f(3x) = 5 - (2 \( \times \) 3k)

f(3k) = 5 - 6k

আবার, f(x) = 5 - 2x

=> f(k + 1) = 5 - 2 (k + 1)

=> f(k + 1) = 5 - 2k - 2

f(k + 1) = 3 - 2k

প্রশ্নমতে, 5 - 6x = 3 - 2k

=> 6k - 2k = 5 - 3

=> 4k = 2

k = 1/2

অতএব, f(k) = 5 - 2k

=> f(k) = 5 - \((2 \times \frac{1}{2})\)

=> f(k) = 5 - 1

f(k) = 4