# application of differentiation in economics

#### helloprajna

How to solve this problem?
If x be the labour, y be its charges and $$\displaystyle y=5x^2 -3x$$
then how much charge will there be when we increase the labour by a small amount?
Is the answer like this:- dy= 10x-3dx ?

#### MarkFL

If we use the differential as a linear approximate, we may write

$$\displaystyle \frac{\Delta y}{\Delta x}\approx\frac{dy}{dx}$$ hence:

$$\displaystyle \Delta y\approx(10x-3)\Delta x$$