2TH §4.4 Simplifying square roots

• Wiskunde
• Middelbare school
• havo, vwo
• Leerjaar 2

Program for today

§4.4 Simplifying square roots

§4.4 Exercises 27, 28, 29, S30 and 31

Before doing §4.4 Simplifying square roots,

we do exercise C6, p.139

Next slide

shows it to you

a bit bigger.

Make this task 

right now in your 

Notebook!

TIP:

1. Copy 

the Sketch

2. Fill in all the

lengths of the

sides and

3. Calculate the

AREA. 

Task:

Solution:     

§4.4 Simplifying square roots

In this § you will learn how to write a square root as:

a multiplication of a whole number and a root, like

                         =

The reason why this is allowed and why it is useful, soon follows!

√​50​​​

5√​2​​​

Let's talk business, as usual!

- Open your Textbook and Notebook and

- Do §4.4 Exercise 27 (p.141)   

- Study the Theory on p.140

- Still time left? Go on with 28, etcetera.

In 27 you tried to write 

as a multiplication of a whole number and a root.

This is how it is possible:

                    =                 x       

                   = 2  and so we get the final form:

                     =       

√​40​​​

√​40​​​

√​4​​​

√​10​​​

√​4​​​

√​40​​​

2√​10​​​

You are going to learn this method by practising a lot!

How could we rewrite: 

as a multiplication of a whole number and a root?

So write it in this shape:             = .... x  .   .....

ANS

√​12​​​

√​12​​​

√​​​​

√​12​​​

1. 4√​3​​​
2. 6√​2​​​
3. 2√​3​​​
4. 3√​2​​​

Solution:

=                        x              =  2  x              =   2           

√​12​​​

√​4​​​

√​3​​​

√​3​​​

√​3​​​

Make exercise 28 and 29 and after that ...

Study Method on p.142.

Still time left?

Go on with S30 and 31.

Now we do 28 and 29 together!

First a real root joke.

Your teacher will ask some of you what to fill in here.

So you can check what you just made in your Notebook.

Let's tackle these in the same way!

Now we look back at this exercise, that you just tried to do.

32 is divisible by the square numbers:  4  and  16

4 x 8 = 32 and 16 x 2 = 32

Did you have it correct?

Let's find out together what had to be filled in here!

4 x 8  = 32  and 16 x 2 = 32

16 is the bigger number so we will choose that one

Let's do one more together, 

to see if you understand it.

Simplify 

ANS

√​63​​​

√​63​​​

I simplify

Explanation:

                =             x          =         3  x              =  

√​63​​​

√​9​​​

√​7​​​

√​7​​​

3√​7​​​

Homework

Do §4.4 Exercises 27, 28, 29, S30 and 31

Don't forget to CHECK your work with the fabulous 

Solutions book.