The exponential function occurs very frequently in mathematical models of nature and society.

So, how to calculate the slope when you don’t know derivative?

example: Differentiate the function example:

take derivative of both sides take ln of both sides ?

Differentiate y = ln(x 3 + 1). example: To use the Chain Rule, we let u = x Then, y = ln u. example: Find:

Differentiate example:

If we first simplify the given function using the laws of logarithms, the differentiation becomes easier

example: Thus, f ’(x) = 1/x for all x ≠ 0. The result is worth remembering:

a logarithmic function with base a in terms of the natural logarithmic function: example:

LOGARITHMIC DIFFERENTIATION 1.Take natural logarithms of both sides of an equation y = f(x) and simplify. 2. Differentiate implicitly with respect to x. 3. Solve the resulting equation for y’. example: differentiate Since we have an explicit expression for y, we can substitute and write If we hadn’t used logarithmic differentiation the resulting calculation would have been horrendous.

example: