Respuesta :

Answer:

True.

Step-by-step explanation:

If a function is multiplicative then it hold following properties

1.f(1)=1

2.[tex]\f(a\cdot b)=f(a)\cdot f(b)[/tex] hold for all a and b when  even a and b are not co-prime.

Let [tex]\sigma(n)[/tex] is a function of  sum of divisor of n

[tex]\sigma (n)[/tex]=Sum of divisor of n

If n=1 then

[tex]\sigma (1)=1[/tex]

It is satisfied first property.

Suppose n=9

Then divisor of 9=1,3,9

Sum of divisor=1+3+9=13

Divisor of 3=1,3

Sum of divisors of 3=1+3=4

[tex]\sigma (9)=13[/tex]

[tex]\sigma (3)\cdot \sigma(3)=4\cdot 4=16[/tex]

Hence, [tex]\sigma (a\cdot b)\neq \sigma(a)\cdot \sigma(b)[/tex]

Therefore, [tex]\sigma(n)[/tex] is not a multiplicative function.

Hence, given statement is true.