The power
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Name: ______________________________________ Subject: _______________________ Date: _______
Write on the right side what is missing.
1. Concept of the power
When we see the picture, we wonder: how many oarsmen participate in the regattas? There are 4 oarsmen in each of the four trawlers, then in total there are 4 x 4 = 16 oarsmen, This can also be written as: 42 and it is read "four to the power of two" .
The powers are products that are all equal factors.
Example: 5 x 5 = 52; 6 x 6 x 6 = 63;
7 x 7 x 7 x 7 = 74.
Do these problems on a paper and write the solution:
1. The power 42 is... |
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2. The power 24 is... |
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3. The power 53 is... |
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4. The power 35 is... |
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5. The power 32 is... |
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6. The power 23 is... |
2. - Elements of the power
In the power
53 we distinguish the base, which is 5 and the exponent, which is 3.
In this case 53 = 5 x 5 x 5. The base (5) is the number that is repeated in the multiplication.
The exponent (3) is the number of times that we must multiply.
1. In the power 73 the 7 is... |
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2. In the power 73 the 3 is... |
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3. In 84 the 8 is... |
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4. In 84 the 4 is... |
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5. In 52 the 2 is.... |
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6. In 52 the 5 is... |
3. - Perfect Squares
The powers with exponent 2 are called perfect squares.
In the picture, we see that the square of 2 (22) is 4, and the square of 3 (32) is 9, and the square of 4 (42) is 16. We can check it by counting the small squares.
When we studied the multiplication tables, we learned that 7 x 7 = 49. Now we can express it as: 72.
Exercises:
1. The power 52 = |
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2. The power 82 = |
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3. The power 62 = |
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4. The power 92 = |
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5. The power 72 = |
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6. The power 102 = |
4. - Squares and cubes
In the left picture, we see a square of 2 cm long and 2 cm width. In total there are 4 small squares of 1 cm side. 2 cm x 2 cm = 4 cm2
In the right picture, we see a cube that is 2 cm long, 2 cm wide and 2 cm high. In total, how many small cubes are there? Count them and you will see that there are 8 cubes. 2 x 2 x 2 = 23 = 8. 23 = 8.
Exercises:
1. 52 = |
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2. 53 = |
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3. 63 = |
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4. 62 = |
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5. 72 = |
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6. 73 = |
| Educational applications |
Matematics |
In Spanish | Interactive
®Arturo Ramo García.-Record of intellectual property of Teruel (Spain)
No 141, of 29-IX-1999
Plaza Playa de Aro, 3, 1º DO 44002-TERUEL