Let $f:N \to N$ be a function such that $f(m + n) = f(m) + f(n)$ for every $m,\,\,n \in N.$ If $f(6) = 18,$ then $f(2).f(3)$ is equal to

JEE MATHEMATICS MCQ: FUNCTIONS

1 Hard

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Application +4 | -1

Let

f:N \to N

be a function such that

f(m + n) = f(m) + f(n)

for every

m,\,\,n \in N.

f(6) = 18,

then

f(2).f(3)

is equal to

View answer and explanation

Correct option: B

Option B (54) is correct because by using the given functional equation and the value of f(6), we can find f(2) and f(3) and then multiply them.

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