Given f(x) below, find f ′(x). Homework Help ✎
f(x) = −x
f(x) = 0
f(x) = 9x + sin x
You should know by now that a derivative is a slope function. Notice that this is a linear equation, and linear equations have constant slopes.
SImilarly, this is a horizontal line. What is the slope of a horizontal line? That will also be the derivative.
Recall that the derivative of sin(x) is cos(x).