Question

Differentiate the following functions with respect to x:

y = ln7x

Answer 1

dy(u(x))/dx = (dy/du)(du/d) chain rule

u=7x, y(u(x)) = ln(7x)

dy/du = 1/7x, du/dx=7

dy/dx = 1/x

or y = ln(7) + ln(x)

derivative of constant is 0

d ln(x)/dx = 1/x