# 1TH/vwo §8.5 Powers of negative numbers

To understand §8.5 better, we first shortly look back at
POWERS.
Because .... what are powers again?!
Powers were explained earlier this year, in §7.2
Let's repeat that explanation first!
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Slide 1: Slide
WiskundeMiddelbare schoolhavo, vwoLeerjaar 1

This lesson contains 33 slides, with interactive quizzes and text slides.

Lesson duration is: 45 min

## Items in this lesson

To understand §8.5 better, we first shortly look back at
POWERS.
Because .... what are powers again?!
Powers were explained earlier this year, in §7.2
Let's repeat that explanation first!

53=....
timer
0:20
A
125
B
15
C
625

#### Slide 5 -Slide

Who's right about: the square of -3 ?
Paulo says: 9
Sabine says: -9
timer
0:20
A
Sabine
B
both
C
Paulo
D
neither

explanation:

#### Slide 7 -Slide

-           = 25      A
-           = - 25   B
-           = 10       C
-           = - 10    D    Fill in the good answer in the next slide.
52
52
52
52

= ...
52
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0:20
A
25
B
- 25
C
10
D
- 10

#### Slide 9 -Quiz

explanation:

-         =    -  5 x 5 = - 25
So the key to the answer is that only 5 is squared, but not
the minus sign!!
Next is the ORDER of OPERATIONS (volgorde van bewerkingen).
52

#### Slide 11 -Slide

After this short REFRESH, we are in §8.5 now.

#### Slide 15 -Slide

After all this squaring ......

+ we'll deal with higher powers too!

#### Slide 16 -Slide

in the same way do:
=  ............
43
timer
0:30

timer
0:30
(4)3
A
64
B
-64
C
-12
D
12

#### Slide 18 -Quiz

=  -4 x -4 x -4 = -64
(4)3

#### Slide 19 -Slide

=   -   4 x 4 x 4 = -64
= -4 x -4 x -4 = -64
So, do             and                    give the same outcome?!
Indeed, they do!!
43
(4)3
43
(4)3

#### Slide 21 -Slide

Let's study a few more difficult tasks together.
For this it is important to work it out on paper,
just like on a test!

#### Slide 22 -Slide

COPY and MAKE in your NOTEBOOK:
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1:00

#### Slide 23 -Slide

This is the Solution:

#### Slide 24 -Slide

this is a Fotovraag:

Then WORK IT OUT, TAKE A PICTURE AND SEND IT IN IN NEXT SLIDE.

timer
1:30

#### Slide 27 -Slide

HOMEWORK (preparing for next Fridays test about Ch8+9)
Make:
p.68/69 Mixed exercises:
+ exercises 48 and 50  and
CHOOSE 3 of the remaining exercises (preferably the ones you are
not that good at, yet).
+  a little ADVISE on the homework follows.

#### Slide 28 -Slide

The exercises e. t/m. h contain more than one
operation.
Work it out completely in your NOTEBOOK!
Not just the answer. Also see next slide!

#### Slide 30 -Slide

HOMEWORK TIME
H/V:       41 t/m 45
VWO:     42 t/m 46

#### Slide 31 -Slide

As you can see, for 45 and 46 the CALCULATIONS are of the greatest importance!
So, when making them, don't just give the answers but show
all the steps it takes, to get the answer!