The definition of derivative can lead us to the derivation of the rules of differentiation or the algebraic
techniques of differentiation.
ALGEBRAIC TEHCNIQUES OF DIFFERENTIATION
ALGEBRAIC TEHCNIQUES OF
DIFFERENTIATION
EXAMPLES
A. Derivative of a Constant
If 𝑓(π‘₯) = π‘˜, where π‘˜ is a real
number, then 𝑓′(π‘₯) = 0
𝑓(π‘₯) = 3
𝒇′(𝒙) = 𝟎
B. Derivative of a Power Function
(Power Rule)
If 𝑓(π‘₯) = π‘₯𝑛
, where 𝑛 is a real
number, then 𝑓′(π‘₯) = 𝑛π‘₯π‘›βˆ’1
𝑓(π‘₯) = π‘₯2
𝑓(π‘₯) = 2π‘₯2βˆ’1
𝒇(𝒙) = πŸπ’™
C. Derivative of the Sum or
Difference of Functions
If 𝑓 and 𝑔 are functions and 𝑝 is a
function defined by 𝑝(π‘₯) = 𝑓(π‘₯) Β±
𝑔(π‘₯) then 𝑝′(π‘₯) = 𝑓′(π‘₯) Β± 𝑔′(π‘₯)
𝑓(π‘₯) = 3π‘₯4
βˆ’ 2π‘₯3
+ 4π‘₯2
βˆ’ 12π‘₯ βˆ’ 5
𝑓′(π‘₯) = (4)(3)(π‘₯4βˆ’1) βˆ’ (3)(2)(π‘₯3βˆ’1) + (2)(4)(π‘₯1βˆ’1) βˆ’ 0
𝒇′(𝒙) = πŸπŸπ’™πŸ‘
βˆ’ πŸ”π’™πŸ
+ πŸ–π’™
D. Derivative of the Product of Two
Functions
If 𝑓 and 𝑔 are functions and 𝑝 is a
function defined by 𝑝(π‘₯) = 𝑓(π‘₯) βˆ™
𝑔(π‘₯) then 𝑝′(π‘₯) = [𝑓(π‘₯) βˆ™ 𝑔′(π‘₯)] βˆ™
[𝑓′(π‘₯)𝑔(π‘₯)]
𝑓(π‘₯) = (2π‘₯2
+ 1)(4π‘₯2
+ 2)
𝑓′(π‘₯) = (2π‘₯2
+ 1)[(4)(2)(π‘₯2βˆ’1)] + [(2)(2)(π‘₯2βˆ’1)](4π‘₯2
+ 2)
𝑓′(π‘₯) = (2π‘₯2
+ 1)(8π‘₯) + (4π‘₯)(4π‘₯2
+ 2)
𝑓′(π‘₯) = 16π‘₯2
+ 8π‘₯ + 16π‘₯2
+ 8π‘₯
𝑓′(π‘₯) = 32π‘₯2
+ 16π‘₯
E. Derivative of the Quotient of
Two Functions
If 𝑓 and 𝑔 are functions and 𝑝 is a
function defined by 𝑝(π‘₯) =
𝑓(π‘₯)
𝑔(π‘₯)
where 𝑔(π‘₯) β‰  0, then
𝑝′(π‘₯) =
𝑔(π‘₯)𝑓′(π‘₯)βˆ’π‘“(π‘₯)𝑔′(π‘₯)
[𝑔(π‘₯)]2
𝑓(π‘₯) =
2π‘₯ βˆ’ 3
4π‘₯ + 1
𝑓′(π‘₯) =
(4π‘₯ + 1)(2) βˆ’ (2π‘₯ βˆ’ 3)(4)
(4π‘₯ + 1)2
𝑓′(π‘₯) =
(8π‘₯ + 2) βˆ’ (8π‘₯ βˆ’ 12)
(4π‘₯ + 1)(4π‘₯ = 1)
𝑓′(π‘₯) =
14
16π‘₯2 + 8π‘₯ + 1

The algebraic techniques module4

  • 1.
    The definition ofderivative can lead us to the derivation of the rules of differentiation or the algebraic techniques of differentiation. ALGEBRAIC TEHCNIQUES OF DIFFERENTIATION ALGEBRAIC TEHCNIQUES OF DIFFERENTIATION EXAMPLES A. Derivative of a Constant If 𝑓(π‘₯) = π‘˜, where π‘˜ is a real number, then 𝑓′(π‘₯) = 0 𝑓(π‘₯) = 3 𝒇′(𝒙) = 𝟎 B. Derivative of a Power Function (Power Rule) If 𝑓(π‘₯) = π‘₯𝑛 , where 𝑛 is a real number, then 𝑓′(π‘₯) = 𝑛π‘₯π‘›βˆ’1 𝑓(π‘₯) = π‘₯2 𝑓(π‘₯) = 2π‘₯2βˆ’1 𝒇(𝒙) = πŸπ’™ C. Derivative of the Sum or Difference of Functions If 𝑓 and 𝑔 are functions and 𝑝 is a function defined by 𝑝(π‘₯) = 𝑓(π‘₯) Β± 𝑔(π‘₯) then 𝑝′(π‘₯) = 𝑓′(π‘₯) Β± 𝑔′(π‘₯) 𝑓(π‘₯) = 3π‘₯4 βˆ’ 2π‘₯3 + 4π‘₯2 βˆ’ 12π‘₯ βˆ’ 5 𝑓′(π‘₯) = (4)(3)(π‘₯4βˆ’1) βˆ’ (3)(2)(π‘₯3βˆ’1) + (2)(4)(π‘₯1βˆ’1) βˆ’ 0 𝒇′(𝒙) = πŸπŸπ’™πŸ‘ βˆ’ πŸ”π’™πŸ + πŸ–π’™ D. Derivative of the Product of Two Functions If 𝑓 and 𝑔 are functions and 𝑝 is a function defined by 𝑝(π‘₯) = 𝑓(π‘₯) βˆ™ 𝑔(π‘₯) then 𝑝′(π‘₯) = [𝑓(π‘₯) βˆ™ 𝑔′(π‘₯)] βˆ™ [𝑓′(π‘₯)𝑔(π‘₯)] 𝑓(π‘₯) = (2π‘₯2 + 1)(4π‘₯2 + 2) 𝑓′(π‘₯) = (2π‘₯2 + 1)[(4)(2)(π‘₯2βˆ’1)] + [(2)(2)(π‘₯2βˆ’1)](4π‘₯2 + 2) 𝑓′(π‘₯) = (2π‘₯2 + 1)(8π‘₯) + (4π‘₯)(4π‘₯2 + 2) 𝑓′(π‘₯) = 16π‘₯2 + 8π‘₯ + 16π‘₯2 + 8π‘₯ 𝑓′(π‘₯) = 32π‘₯2 + 16π‘₯ E. Derivative of the Quotient of Two Functions If 𝑓 and 𝑔 are functions and 𝑝 is a function defined by 𝑝(π‘₯) = 𝑓(π‘₯) 𝑔(π‘₯) where 𝑔(π‘₯) β‰  0, then 𝑝′(π‘₯) = 𝑔(π‘₯)𝑓′(π‘₯)βˆ’π‘“(π‘₯)𝑔′(π‘₯) [𝑔(π‘₯)]2 𝑓(π‘₯) = 2π‘₯ βˆ’ 3 4π‘₯ + 1 𝑓′(π‘₯) = (4π‘₯ + 1)(2) βˆ’ (2π‘₯ βˆ’ 3)(4) (4π‘₯ + 1)2 𝑓′(π‘₯) = (8π‘₯ + 2) βˆ’ (8π‘₯ βˆ’ 12) (4π‘₯ + 1)(4π‘₯ = 1) 𝑓′(π‘₯) = 14 16π‘₯2 + 8π‘₯ + 1