Find the derivative of f(x) = 5x + 9 at x = 2.

Solution:

The derivative of f(x) is given as

df(x)/dx = d(5x + 9)/dx

f’(x) = df(x)/dx = d(5x)/dx + d(9)/dx

f’(x) = 5dx/dx + d(9)/dx

f’(x) = 5 + 0

f’(x) = 5 is a constant

At x = 5 the derivative of the function f(x) = 5x + 9 at x = 2 is 5

Find the derivative of f(x) = 5x + 9 at x = 2.

Summary:

The derivative of f(x) = 5x + 9 at x = 2 is 5