6 Product and Quotient Rules v2.notebook...Topic 2.8: The Product Rule Topic 2.9: The Quotient Rule...

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6_Product_and_Quotient_Rules_v2.notebook 1 October 24, 2019 Product and Quotient Rules Lesson objectives Teachers' notes College Board ® Topics: Topic 2.7: Derivatives of cos x, sin x, e x , and ln x Topic 2.8: The Product Rule Topic 2.9: The Quotient Rule Topic 2.10: Finding the Derivatives of Tangent, Cotangent, Secant, and/or Cosecant Functions Topic 2.2: Defining the Derivative of a Function and Using Derivative Notation College Board ® Learning Objectives: FUN3: Recognizing opportunities to apply derivative rules can simplify differentiation. FUN3.B: Calculate derivatives products and quotients of differentiable functions Teachers' notes Lesson objectives Subject: Topic: Grade(s): Prior knowledge: Crosscurricular link(s): Type text here Type text here Type text here Type text here Type text here Lesson notes: Apply the product and quotient rules algebraically for polynomial, power, sine, cosine, tangent, exponential and logarithmic functions

Transcript of 6 Product and Quotient Rules v2.notebook...Topic 2.8: The Product Rule Topic 2.9: The Quotient Rule...

Page 1: 6 Product and Quotient Rules v2.notebook...Topic 2.8: The Product Rule Topic 2.9: The Quotient Rule Topic 2.10: Finding the Derivatives of Tangent, Cotangent, Secant, and/or Cosecant

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Product and Quotient Rules

Lesson objectives Teachers' notes

College Board® Topics:Topic 2.7: Derivatives of cos x, sin x, ex, and ln xTopic 2.8: The Product RuleTopic 2.9: The Quotient RuleTopic 2.10: Finding the Derivatives of Tangent, Cotangent, Secant, and/or Cosecant FunctionsTopic 2.2: Defining the Derivative of a Function and Using Derivative NotationCollege Board® Learning Objectives:FUN­3: Recognizing opportunities to apply derivative rules can simplify differentiation. FUN­3.B: Calculate derivatives products and quotients of differentiable functions

Teachers' notesLesson objectives

Subject:

Topic:

Grade(s):

Prior knowledge:

Cross­curricular link(s):

Type text here

Type text here

Type text here

Type text here

Type text here

Lesson notes:

Apply the product and quotient rules algebraically for polynomial, power, sine, cosine, tangent, exponential and logarithmic functions

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1. The Product Rule:If a function is the product of two differentiable functions

then the derivative is “the first times the derivative of the second plus the second

times the derivative of the first.”

PRODUCT and QUOTIENT RULES

Shorthand

In building our derivative toolkit, we are ready for the power tools! Let’s go. . .

or “f prime • g, plus f • g prime”

Topic 2.8: The Product RuleTopic 2.9: The Quotient Rule

EX #1: Find the derivative of the following.

A) B)

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EX #1: Find the derivative of the following.

C) D)

Since multiplication and addition are both commutative, the product rule is hard to mix up, unless you misunderstand the rules. It’s easy, just take turns on the factors. . . One derivative at a time for each term.

A Cautionary Tale . . .

Just don’t confuse the product rule with the limit properties. The product rule is incorrectly interpreted as follows: “The derivative of a product of two functions f and g is the product of the derivatives of f and g.

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2. The Quotient Rule:If a function is the quotient of two differentiable functions then the derivative is “the denominator times the derivative of the numerator minus the numerator times the derivative of the denominator, all divided by the denominator, squared.

Low di Hi ­ Hi di LowLow Low

Low = 0HI LO

d dx =

Shorthand

EX #2: Use the quotient rule to differentiate.

A) B)

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C) D)

HO di HI ­ HI di HOHO HO

; HO = 0HI HO

d dx =

More Things to Contemplate!

Subtraction is not commutative, you have to be careful with the quotient rule.

The quotient rule is NOT to be interpreted as follows: “The derivative of a quotient of two functions f and g is the quotient of the derivatives of f and g.

Another Fun Mnemonic:

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EX #3: Find an equation of the tangent line to the graph of f at the point

EX #4: Use the quotient rule to develop the rules for the remaining four trigonometric functions. Rewrite each of the functions in terms of sine and cosine and differentiate.

A)

B)

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EX #4: Use the quotient rule to develop the rules for the remaining four trigonometric functions. Rewrite each of the functions in terms of sine and cosine and differentiate.

C)

D)

Memorize the derivatives for all six trigonometric functions.

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Function Rewrite Differentiate Simplify

EX #5: Decomposing Fractions with Single Term Denominators Using the Constant Multiple Rule to Rewrite

Higher Order Derivatives

Position function

Velocity function

Acceleration function

First derivative:

Second derivative:

Third derivative:

Fourth derivative:

Did you realize that it is possible to take the derivative of a derivative? We will need this ability in the study of particle motion and objects in motion, especially related to physics in the near future.

Topic 2.2: Defining the Derivative of a Function and Using Derivative Notation

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A.) Find f ''(x) given

B.) Find if

EX #6: For each of the following, find the stated derivative.

C.)

D.) Find given

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EX #7: A potato launcher fires a potato downward, from the top of a 112‑foot tall building. The potato hits the ground in two seconds. Find the initial velocity of the potato. The position function is given as where distance, s(t) is in feet, and time, t is in seconds.