1TH/Vwo §7.2 Powers

Now comes a powerful paragraph!
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Slide 1: Tekstslide
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In deze les zitten 33 slides, met interactieve quizzen en tekstslides.

time-iconLesduur is: 30 min

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Now comes a powerful paragraph!

Slide 1 - Tekstslide

§7.2 Powers
Homework:  9  t/m  17

Slide 2 - Tekstslide

First a task about §7.1
In the next slide send in your
CALCULATION + ANSWER to the task!
NOTE:            this symbol (a point) means 'multiplying'.
So, for example:   
56=30

Slide 3 - Tekstslide

2+6(7+3)=..

Slide 4 - Woordweb

2 + 6 x (7 + 3) = ...
2 + 6 x 10 =                      first the addition between the brackets 
2 + 60 =                            then the multiplication
62                                       finally the addition is done

Slide 5 - Tekstslide

2 + 6 x (7 + 3) = ...
NOT like this however:                       
2 + 6 x 10 =  
60 =                  
2 + 60 =                            
62    ,  because 60  is NOT equal to 62, as is stated here!                                

Slide 6 - Tekstslide

Here is a table with Length = 2 m  and also Width = 2 m.
The Area (=oppervlakte) = 2 x 2 = 4           
Multiplying a number by itself -in this case 2- is called:
SQUARING a number.
The result is the SQUARE of a number. Let's look at a few more examples!
'Square'  is in dutch:      'kwadraat'.
m2

Slide 7 - Tekstslide


'squaring' in dutch we call this:
'kwadrateren'.  Or:   'het kwadraat nemen van' .

Slide 8 - Tekstslide

In the next slide
 give the answers to these 5 exercises.

Slide 9 - Tekstslide

The 5 answers to the SQUARES are:
timer
0:30
A
1, 2, 3, 4 and 5
B
1, 4, 9, 16 and 25
C
2, 4, 6, 8 and 10

Slide 10 - Quizvraag

Solutions:
So, for example:
the SQUARE of 5 is
5 x 5 = 25.

Slide 11 - Tekstslide

However ...
sometimes you want to multiply a number by itself more than once. Then we can use a similar Notation as for the Square:
+  For example:  3 x 3 x 3 x 3 =            = 81
+  See the next slide for more! New examples and the new Words that come with this. 
+  Like the word: POWER.
34

Slide 12 - Tekstslide

Slide 13 - Tekstslide

Question:
What is a powerful idea during a long and tiring day?
Solution - see next slide!

Slide 14 - Tekstslide

A POWERNAP!

Slide 15 - Tekstslide

Slide 16 - Tekstslide

Slide 17 - Tekstslide

is the same as ........
43
timer
0:20
A
4 x 4 x 4
B
4 + 4 +4
C
4 x 3
D
64

Slide 18 - Quizvraag

Explanation:
        means the same as:
4 x 4 x 4, 
but it also means: 64, because that is the outcome.
It doesn't mean 4 + 4 + 4, which you could write as 3 x 4 = 12.
Once more:                      = 4 x 4 x 4 = 64
Remember: a POWER is about multiplying, not adding!
43
43

Slide 19 - Tekstslide

Squaring a number is an example of
raising to a power.
A
true
B
not true

Slide 20 - Quizvraag

Solution:

Both are examples of raising to a power!
34=3x3x3x3=81
52=5x5=25

Slide 21 - Tekstslide

is the same as .....
24
timer
0:20
A
8
B
2 x 2 x 2 x 2
C
16
D
2 + 2 + 2 + 2

Slide 22 - Quizvraag

Explanation:
        is the same as:
+   2 x 2 x 2 x 2 , because a power is a multiplication, that is repeated.
+   16, because that's the outcome.
+   however, it's not about adding, so not 2 + 2 + 2 +2.
24

Slide 23 - Tekstslide

REMEMBER THIS? IT'S FROM §7.1!



WHERE DO THE POWERS FIT IN IN THIS LIST?!
THINK ABOUT THIS!

Slide 24 - Tekstslide

Watch below: between the 'brackets' and the 'multiplying/dividing' the POWERS are placed!
So it comes 2nd in place. Brackets go first always!

Slide 25 - Tekstslide

THINK about this one for a while ... 
You don't have to actually work it out.
Just think about the ORDER in which to work it all out!

Slide 26 - Tekstslide

Here is the Solution:
(Study it carefully, because you're going to make one yourself!)

Slide 27 - Tekstslide

FOTOVRAAG:
1. Work this one out on paper.
2. Take a pic and
3. Send it in in next slide!

timer
1:30

Slide 28 - Tekstslide

My work in a Photo:

Slide 29 - Open vraag

Solution:
The POWERS between the BRACKETS have to be worked out first!
Following the PRIORITY rules we get:
7 x ( 36 - 32) = 7 x 4 = 28
A common mistake would be: 
7 x ( 12 - 10 ) = 7 x 2 = 14   In this case you've done 6 x 2 and 2 x 5 instead of
calculating POWERS!  Another common mistake:
                                                        =   36 - 25 = 7 x 11 = 77      because here '7' disappeared for a while!?
7x(6225)

Slide 30 - Tekstslide

Solution:
A common mistake would be: 
7 x ( 12 - 10 ) = 7 x 2 = 14   In this case you've done 6 x 2 and 2 x 5 instead of
calculating POWERS!  Another common mistake:
                                                        =   36 - 25 = 7 x 11 = 77      because here '7' disappeared for a while!?
7x(6225)

Slide 31 - Tekstslide

As for 16, above, mind the remark :
'Calculate as in the example above' !
So don't just give the answers -they are in the Solutionsbook too- but show the process of Calculating!
So: show your calculation. It also helps to gain points in the next test!

Slide 32 - Tekstslide

Homework time.
+  Do §7.2 now.
+   You may skip:   12 and 15 as we have done a lot 
     together!


Slide 33 - Tekstslide