Differentiation Formulas : We will begin this section with some basic properties and formulas.  We will give the properties & formulas in this section in both "prime" notation & "fraction" notation.

Properties

1)   (f ( x) ± g ( x ))′ ) = f ′ ( x ) ±  g ′ ( x )   OR  d ( f (x ) ± g ( x )) = df/dx ± dg/ dx

In other terms, to differentiate a sum or difference all we have to do is differentiate the individual terms & then put them back together with the suitable signs.  Note that this property is not limited to two functions.

2)   (cf ( x ))′ = cf ′ ( x )     OR   d (cf ( x ))/dx = c df/dx , c is any number

In other terms, we can "factor" a multiplicative constant out of derivative if we have to.

Note as well that we have not involved formulas for the derivative of products or quotients of two functions here. The derivative of product or quotient of two of functions is not the product or quotient of the derivatives of individual pieces