Refresh

• Wiskunde
• Middelbare school
• havo
• Leerjaar 3

Before we start the chapter we need to remember some of the things we have learnt before.

• When doing calculations we must remember the order of calculation BIDMAS
• when we raise a negative number to a power we need to see id power is odd or even
• Add fractions
  
• Multiply fractions
• Add square roots
• Multiply square roots
• write formulas shorter

Order of calculation

e.g.  32- 4 x (16-5x2) = 

first do what's in brackets

32 - 4 x(16-10) = 

32 - 4 x 6 = 

then do multiplication

32 - 24 = 

and finally the subtraction  32 -24 = 8

Even powers

and

5​2​​=5⋅5=25

(−5)​2​​=(−5)⋅(−5)=25

Odd Powers

but

5​3​​=5⋅5⋅5=125

(−5)​3​​=(−5)⋅(−5)⋅(−5)=−125

Adding fractions

To add fractions both fractions need to have the same denominator. 

(that is the number on the bottom row of the fraction!)

Multiplying fractions

Multiply numerators together and divide by 

denominators multiplied together

adding square roots

the numbers under the square root sign must be the same

then you can add them together

multiplying square roots

square roots can be multiplied by multiplying the numbers under the root signs.

Finally 

when you need to shorten formulas you will need to remember 

• you can only add terms  if they are like
  
• you need to remove brackets by multiplying
• be careful with powers

Homework 

Do all refresh exercises R1 t/m R7