1.Relation and Function
normal

$f$ એ $x$ અને $y$ ની બધી જ વાસ્તવિક કિમત માટે $f(xy) = \frac{f(x)}{y}$ શક્ય છે. જો $ f(30) = 20,$ તો $f(40)$ ની કિમત .......... થાય.

A

$15$

B

$20$

C

$40$

D

$60$

Solution

$f(x y)=\frac{f(x)}{y}$

Put $y=3 $ and $ x=10$

$f(30)=\frac{f(10)}{3} $ 

$\Rightarrow f(10)=3 \times f(30)=3 \times 20=60$

Now put $y=4 $ and $ x=10$

$f(40)=\frac{f(10)}{3}$ 

$ \Rightarrow f(40)=\frac{60}{4}=15$

Standard 12
Mathematics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.