# Exponential functions (t3g)

Exponential functions

March 24th
t3g
11:00
Camera ON
1 / 24
Slide 1: Tekstslide
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In deze les zitten 24 slides, met interactieve quizzen en tekstslides.

Lesduur is: 60 min

## Onderdelen in deze les

Exponential functions

March 24th
t3g
11:00
Camera ON

#### Slide 1 -Tekstslide

Schedule
• Announcements                                             5 min
• Review: trigonometry                                 10 min
• Exponential functions                                15 min

Quiz questions
• Practice                                                             20 min
Break-out rooms
• Discuss exercise                                            10 min

Programme

Ch.8.1/8.2 today
Review Monday

#### Slide 3 -Tekstslide

Test ch.3
Thursday, April 13th, 5th period

Are you in steunuur? Mandatory anyway

#### Slide 4 -Tekstslide

Video in Teams!
Files - Lesmateriaal - Answers test ch.4-6-7

#### Slide 5 -Tekstslide

Last lesson's
Intended Learning Outcomes

At the end of the lesson you could...
1. Apply trigonometric calculations in contexts and situations

#### Slide 6 -Tekstslide

You want to know
the length of LM.
What do you use?
A
Tangent
B
Sine
C
Inverse sine
D
Inverse cosine

You want to know
the size of
What do you use?
A.
A
Tangent
B
Sine
C
Inverse sine
D
Inverse cosine

#### Slide 8 -Quizvraag

You want to know
the length of KM.
What do you use?
A
Inverse sine
B
Sine
C
Inverse tangent
D
Cosine

#### Slide 9 -Quizvraag

Today's
Intended Learning Outcomes

At the end of the lesson you can...
1. Set up your own exponential formula
2. Recognize and apply exponential growth vs. decay
3. Combine percentages with exponential formulas

#### Slide 10 -Tekstslide

Formulas:
linear vs. exponential

#### Slide 11 -Tekstslide

Formulas:
linear vs. exponential

a = gradient                                                    g = growth factor
b = y-intercept                                              b = initial value
y=ax+b
N=bgt

#### Slide 12 -Tekstslide

Example
linear vs. exponential
__________________________________________________________________
2 = gradient                                                                         2 = growth factor
5 = y-intercept                                                                   5 = initial value
y=2x+5
N=52t

#### Slide 13 -Tekstslide

Example
linear vs. exponential
__________________________________________________________________
2 = gradient                                                                         2 = growth factor
5 = y-intercept                                                                   5 = initial value
y=2x+5
N=52t

#### Slide 14 -Tekstslide

Exponential formulas

Describe (in general terms) what you think happens to the graph when:
a. g > 1
b. 0 < g < 1
b. g < 0
N=bgt

#### Slide 15 -Tekstslide

Describe what you think happens to the graph when:
a. g > 1
b. 0 < g < 1
b. g < 0
N=bgt

#### Slide 16 -Open vraag

www.geogebra.org/graphing

#### Slide 17 -Tekstslide

Growth factor

g > 1: only increasing

0 < g < 1: only decreasing

g < 0: impossible
N=bgt

#### Slide 18 -Tekstslide

Percentages can also be written as a growth factor!

Example:
When you keep increasing a price by 25%,
you're doing                   each time
1.25

#### Slide 19 -Tekstslide

Percentages can also be written as a growth factor!

Example:
When you keep decreasing a price by 14%,
you're doing                   each time
0.86

#### Slide 20 -Tekstslide

Anouk starts with 500 euros in the bank. She receives a positive 2% interest rate per year.
N is amount of money, t is time in years.
What is the formula for this situation?
A
N=2500t
B
N=5002t
C
N=1.02500t
D
N=5001.02t

#### Slide 21 -Quizvraag

Thirza starts with 200 euros in the bank. She loses 13% each month due to a gambling addiction. :(
What is the corresponding formula?
Again: N is amount of money, t is time in months.
A
N=2000.13t
B
N=20013t
C
N=2000.87t
D
N=20087t

#### Slide 22 -Quizvraag

Practice
Chapter 8

Everyone:
Do 2, 5 and 8

Afterwards:
Math A/C
Do 9, 10, 13, 14,
15, 16 and 18

Math B/D
Do 9, 10, 13, 16 and 18