5
3
27
243
MATH
(1/4)­3
1
Index
Radical Sign
Radicand
2
SE
ERA
FOR S
ER
ANSW
1. What is the index of 5
2. What is the radicand of 24
3. Explain the meaning of the index.
The index tells us which root to take.
4. Write 2 as a square root, a cube root, and a fourth root.
22 = 4, √4 = 2
23 = 8, ∛8 = 2
24 = 16, ∜16 =2
3
4
9
16
25
36
49
64
81
100
121
8
27
64
125
216
343
512
729
1000
1331
16
81
256
625
1296
2401
4096
6561
10000
14641
4
What is the square root of 13?
√9
√13
√16
3
?
4
13 is closer to 16 ....... 3.8
3.82 = 14.44 To far away. Let try something smaller
3.72 = 13.69 Try again
3.62 = 12.96 Close enough !!!
5
What is the square root of 41?
√36
6
√41
√49
?
7
41 is closer to 36 ....... 6.4
6.42 = 40.96 Close Enough !!
6
8
27
What is the cube root of 68?
64
125
216
343
512
729
1000
1331
3
√64
4
3
√68
?
3
√125
5
68 is closer to 64 ....... 4.2
4.23 = 74.08 Try Again
4.13 = 68.921 Try Again
4.083 = 67.9173 Close Enough
7
√­16
Calculate √­64
= Error !!!
DOES THIS MEAN WE CAN'T TAKE THE ROOT OF A NEGATIVE NUMBER?
Let Try ∛­64 = ­4
∜­64 = Error
√5 ­64 = ­2.29739....
8
9