Why Memorize Cubes refer to the multiplication of a number 3 times. Cube roots, on the other hand, help us to go the other way. So, for example, the cube of 5 would be the multiplication of the number cube three times and would give us the result 125. The cube root of 125, on the other hand, would give us the number 5. In other words, 5 is multiplied three times and gives us the said number. Memorizing the cubes from 1 to 20 and the cube roots of 1 to 21 would help us to calculate faster and more efficiently.
The cube root of 1 to 20 and the cubes from 1 to 20 are very important and must be memorized by the students. This helps in faster calculations and does away with the need to manually go through long, tedious calculations. Suppose one has the cube table memorized then for a number like 64 the student would not need to sit and calculate the prime factors to find the cube root but can easily do it in their head with the cube from 1 to 20 that they have memorized. This is a very effective technique and should be used by every student.
Following is the 1 to 20 cube root table. Here we provide the cube root from to cube root of 20. This table of cube root till 20 would help the students to solve questions faster and with more ease. The cube roots are given approximately correct up to three decimal points.
Number | Cube Root |
1 | 1 |
2 | 1.260 |
3 | 1.442 |
4 | 1.587 |
5 | 1.710 |
6 | 1.817 |
7 | 1.913 |
8 | 2 |
9 | 2.80 |
10 | 2.154 |
11 | 2.224 |
12 | 2.289 |
13 | 2.351 |
14 | 2.410 |
15 | 2.466 |
16 | 2.520 |
17 | 2.571 |
18 | 2.621 |
19 | 2.668 |
20 | 2.714 |
For a question, where one would need to find 15 cubes, it is very difficult to do such a calculation since it would consume a lot of time. Hence in addition to 1 to 20 cube root table, one must also memorize the 1 to 20 cubes chart. This helps in calculations and allows students to break down complex calculations into simpler parts and use their memory to do these calculations easily and efficiently. The list is as follows:
Number | Cubes |
1 | 1 |
2 | 8 |
3 | 27 |
4 | 64 |
5 | 125 |
6 | 216 |
7 | 343 |
8 | 512 |
9 | 729 |
10 | 1000 |
11 | 1331 |
12 | 1728 |
13 | 2197 |
14 | 2744 |
15 | 3375 |
16 | 4096 |
17 | 4913 |
18 | 5832 |
19 | 6859 |
20 | 8000 |
The cube root of a number refers to a special value that when cubed gives an original number and hence can be considered an opposite of cube which is just the three times multiplication of a number with itself. The cube root is denoted by the radical symbol which is also used for square roots but with a little three that is written on top in order to denote a cube root. Another interesting thing about cube roots is that you can find the cube root of a negative number, unlike square root which cannot be done for a negative number.
The perfect cubes, on the other hand, refer to cubes of whole numbers, and for these numbers, it is relatively easy to find the cube root of the number. While real non zero numbers have only one real cube root, the non-zero complex numbers consist of three cube roots which are also complex. The cube root operative is not distributive either in addition or subtraction and can be taken as a real number in some contexts.
If x is a real number, then there exists a real number y such that x is a cube of y. However, if x and y are considered to be complex, there can be three solutions which are possible, and x would have three different cube roots. If we find the cube of an odd number, then the resulting number would also be odd, and this applies for even numbers as well. If you find a number that ends with 1 to 9 or 000, 625, 875 or 125 then there is a possibility that there are cubes. These observations can be used during calculations to do them quicker.
Q. Cube of 3 plus cube root of 3 is equal to:
Answer: The value of the cube root of 3 is 1.442, and the cube of 3 is 27. Their addition would give 28.442.
1. Why Should Students Memorize the Cube Root of 1 to 20?
Answer: All students must memorize the cube roots of 1 to 20. Although memorizing may take time, it would pay off in the long run. This is because while it is easier to find the cube root of some numbers, the other numbers which are not perfect cubes are very difficult to break down. Hence, if one is asked to calculate the cube root of 8, it is relatively easy. This is because we can easily find out that 2 multiples three times by itself gives 8. However, for a number like 3, it would be not easy to find the cube root.
2. Why Should Students Memorize Cubes of 1 to 20?
Answer: Students should memorize the cubes of 1 to 20. Memorizing the table would not help them make calculations easier but also help them save a lot of time and hassle during examinations. This is primarily done to evade going through long, tedious calculations during examinations. It is easier to find cubes of a smaller number like 2, 3 or 4. But as the numbers get higher, it becomes more and more difficult. Hence, when asked to find the cube of 18 students would find it difficult to work it out during exams. This is where memorization comes in handy and helps the students be more efficient.
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