SECTION 3.1 The Derivative and the Tangent Line Problem.

20
SECTION 3.1 The Derivative and the Tangent Line Problem

Transcript of SECTION 3.1 The Derivative and the Tangent Line Problem.

Page 1: SECTION 3.1 The Derivative and the Tangent Line Problem.

SECTION 3.1The Derivative and the Tangent Line Problem

Page 2: SECTION 3.1 The Derivative and the Tangent Line Problem.

Remember what the notion of limits allows us to do . . .

Page 3: SECTION 3.1 The Derivative and the Tangent Line Problem.
Page 4: SECTION 3.1 The Derivative and the Tangent Line Problem.

Tangency

Page 5: SECTION 3.1 The Derivative and the Tangent Line Problem.

Instantaneous Rate of Change

Page 6: SECTION 3.1 The Derivative and the Tangent Line Problem.

The Notion of a Derivative

Derivative

• The instantaneous rate of change of a function.• Think “slope of the tangent line.”

Definition of the Derivative of a Function (p. 119)

The derivative of at is given by

Provided the limit exists. For all for which this limit exists, is a function of .

Page 7: SECTION 3.1 The Derivative and the Tangent Line Problem.

Graphical Representation

Page 8: SECTION 3.1 The Derivative and the Tangent Line Problem.

f(x)

So, what’s the point?

Page 9: SECTION 3.1 The Derivative and the Tangent Line Problem.

f(x)

Page 10: SECTION 3.1 The Derivative and the Tangent Line Problem.

f(x)

Page 11: SECTION 3.1 The Derivative and the Tangent Line Problem.

f(x)

Page 12: SECTION 3.1 The Derivative and the Tangent Line Problem.

Notation and Terminology

Terminology

differentiation, differentiable, differentiable on an open interval (a,b)

Differing Notation Representing “Derivative”

Page 13: SECTION 3.1 The Derivative and the Tangent Line Problem.

Example 1 (#2b)Estimate the slope of the graph at the points and .

Page 14: SECTION 3.1 The Derivative and the Tangent Line Problem.

Example 2Find the derivative by the limit process (a.k.a. the formal definition).

a.

b.

Page 15: SECTION 3.1 The Derivative and the Tangent Line Problem.

Example 3Find an equation of the tangent line to the graph of at the given point.

Page 16: SECTION 3.1 The Derivative and the Tangent Line Problem.

Graphs of and

𝒇𝒇 ′

Page 17: SECTION 3.1 The Derivative and the Tangent Line Problem.

Graphs of and (cont.)

𝒇 ′ (𝒙 )=𝟐 𝒙

Page 18: SECTION 3.1 The Derivative and the Tangent Line Problem.

Example 4Use the alternative form of the derivative.

Alternative Form of the Derivative

Page 19: SECTION 3.1 The Derivative and the Tangent Line Problem.

When is a function differentiable?

• Functions are not differentiable . . . • at sharp turns (v’s in the function),• when the tangent line is vertical, and• where a function is discontinuous.

Theorem 3.1 Differentiability Implies Continuity

If is differentiable at , then is continuous at .

Page 20: SECTION 3.1 The Derivative and the Tangent Line Problem.

Example 5Describe the -values at which is differentiable.

a.

b.