Chapter 2: Differentiation
Section 2.2: Precise Definition of the Derivative
Example 2.2.2
Apply Definition 2.2.1 to fx=x2+1x+2, to obtain f′c, c≠−2.
Solution
Define the function f
Control-drag fx=… Context Panel: Assign Function
fx=x2+1x+2→assign as functionf
Method 1
Write the mathematical notation for the derivative
Context Panel: Evaluate and Display Inline
Context Panel: Simplify≻Simplify
f′c = 2⁢cc+2−c2+1c+22= simplify c2+4⁢c−1c+22
Method 2
Type fx and press the Enter key.
Context Panel: Differentiate≻With Respect To≻x
Context Panel: Evaluate at a Point≻x=c
fx
x2+1x+2
→differentiate w.r.t. x
2⁢xx+2−x2+1x+22
= simplify
x2+4⁢x−1x+22
→evaluate at point
c2+4⁢c−1c+22
Method 3
Expression palette: Differentiation template Apply to fx and press the Enter key.
Evaluate at x=c as above.
ⅆⅆ x fx
Stepwise solutions
Tools≻Load Package: Student Calculus 1
Loading Student:-Calculus1
Apply the NewtonQuotient command.
Context Panel: Evaluate at a Point≻h=0 (The difference quotient is returned simplified, so the limit is found by setting h to zero.)
NewtonQuotientfx,x=c,h=h
c2+c⁢h+4⁢c+2⁢h−1c+h+2⁢c+2
Application of Definition 2.2.1
Expression palette: Limit template Type the difference quotient
limh→0fc+h−fch = c2+4⁢c−1c+22
The difference quotients in Examples 2.2.1-3 each require different algebraic manipulations for the stepwise computation of the limit.
The difference quotient and its simplification
Write the difference quotient; Press the Enter key.
Context Panel: Evaluate at a Point≻h=0
fc+h−fch
c+h2+1c+h+2−c2+1c+2h
The stepwise simplification of the difference quotient, shown below, is a recital of "addition of fractions by finding a common denominator."
=c+h2+1⋅c+2−c2+1⋅c+h+2c+h+2⋅c+2h
=A−Bh c+h+2⋅c+2, where
A=c3+2⁢c2+2⁢c2⁢h+4⁢c⁢h+h2⁢c+2⁢h2+c+2
B=c3+c2⁢h+2⁢c2+c+h+2
=h c2+4⁢c+c⁢h+2⁢h−1h c+h+2⋅c+2
=c2+4⁢c+c⁢h+2⁢h−1c+h+2⋅c+2
<< Previous Example Section 2.2 Next Example >>
© Maplesoft, a division of Waterloo Maple Inc., 2024. All rights reserved. This product is protected by copyright and distributed under licenses restricting its use, copying, distribution, and decompilation.
For more information on Maplesoft products and services, visit www.maplesoft.com
Download Help Document