3. RADICAL
β’ It is an expression consisting of
a radical sign and radicand.
β’ Its type is π
π, where n is the
index and a is the radicand.
β’ When no index is indicated, the
radical sign indicates a square root.
4. 23
2 β’ 2 β’ 2
π
π
8= Radical
sign
Radicand
Index
Radical
The number 2
is the cube
root of 8.
5. EXAMPLES:
1. 49 = 7
Indicates the principal
square root of 49.
2. 36 = 6
Indicates the principal
square root of 36.
3. 2 2 is not a perfect square
but the value of its square
root can be approximated.
6. EXAMPLES:
1. 9 =
Indicates the principal
square root of 9.
2. 100 =
Indicates the principal
square root of 100.
3
10
8. EXAMPLES:
1.
3
64 = 4
4 is used as a factor three times. 4 is
also considered the principal cube root.
2.
4
81 = 3
3 is used as a factor four times. 3 is
also considered as the principal 4th
root of 81.
3.
5
β32 = β2 If the index is odd, we can get the
principal root of any real number.
4.
3
5
5 is not a perfect cube so we cannot get
the exact cube root. We can only get its
approximate value.
11. IRRATIONAL
NUMBER
It is a number
which cannot
be expressed
as a ratio of
two integers.
Examples:
2,
3
5,
Ο
12. REMEMBER THAT:
β’ The cube root of positive number is positive.
β’ The cube root of negative number is negative.
β’ There is only one real number cube root for each
real number.
β’ When the index is an even number ( like square
root, fourth root, and so on) and the radicand is
positive, there exists a principal root.
13. Tell which number is the index and
which is the radicand.
β’ 4
β’
3
8
β’
5
12
β’
10
7
β’
48
12
β’
5
4
β’
9
3
β’
5
29
β’ 27
β’ 49
β’ 216
β’
3
β125
β’
3 144
96
β’
3
1000
18. Rule:
πβπ
=
π
π π and π π
=
π
πβπ
Where π β 0 and n is a
counting number.
NEGATIVE
EXPONENTS
=
π
π π
E π₯πππππ:
πβπ
=
π
πππ
31. POWER LAW
OF
EXPONENTS
If m and n are positive integers
with no common factor except
1, then for all real numbers b for
which π
π
π is defined,
π
π
π = (π
π
π) π
= (
π
π )
π
or (
π
π π )