Cette leçon contient 10 diapositives, avec diapositives de texte.
La durée de la leçon est: 50 min
Éléments de cette leçon
CH3 Roots
Test Preparation
Slide 1 - Diapositive
Roots
You know what a square root is, and which roots exist.
The square root of 5 is the positive number that when squared equals 5.
You cannot take the square root of a negative number.
Slide 2 - Diapositive
Roots
You know what a cubic root is, and which roots exist.
The cubic root of 5 is the positive number that when raised to the power 3 equals 5. You can take the cubic root of a negative number.
Slide 3 - Diapositive
Adding and Subtracting Roots
You can only add and subtract roots with the same number underneath the square root sign. This works the same way as adding and subtracting like terms.
Slide 4 - Diapositive
Multiplying square roots
When multiplying square roots, you use the rule
If there are numbers in front of the square roots, you multiply those by each other.
Slide 5 - Diapositive
Write as a single square root
You can write numbers as a single square root.
This makes it easier to compare numbers.
Slide 6 - Diapositive
Comparing numbers.
Let me explain!
'This makes it easier to compare numbers', it read on the previous slide.
Now it is possible to compare
to .
It turns out that the first is greater.
Because is greater than !
4√2
2√7
√32
√28
Slide 7 - Diapositive
Simplify square roots
When you simplify a square root, you rewrite the root so you get the smallest possible whole number underneat the root sign.
Slide 8 - Diapositive
Exact or Approximation
When asked for an exact answer, you give your answer as a square root (or a whole number if the square root is a whole number).
When asked for an approximation you type the square root in your calculator and round off the result.
Slide 9 - Diapositive
To get more practice now do:
- SUMMARY p.114/117 if you want explanations too, or:
- Extra exercise p.120/121 if you prefer only exercises.
La durée de la leçon est: 50 min
