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If two non-zero rational numbers a and B satisfy the relation a + B = 0, is their product a * B negative or positive
Their product a * B is negative, for example: - 2 + 2 = 0 - 2 * 2 = - 4
If two non-zero rational numbers a and B satisfy the relation a + B = 0, can you judge whether their product a × B is a positive number or a negative number? If so, please explain the reason. If not, please give an example
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As shown in the figure, how to use a wall (the length of the wall is unlimited) and a 20 m long fence to form a rectangular field with an area of 50 M2?
As shown in the figure, how to use a wall (the length of the wall is unlimited) and a 20 m long fence to form a rectangular field with an area of 50 M2?
As shown in the figure, how to use a wall (the length of the wall is unlimited) and a 20 m long fence to form a rectangular field with an area of 50 M2?
Use m-meter-long fence material to form a green space in the blank space. One is square and the other is round. Which one has a larger area? Why?
It can't be assumed, it can only be expressed by M.
Large round area
Because (for example) suppose that M is 12.56 meters, then the radius of the circle is (12.56 / 3.14 / 2 = 2), and the area is 3.14 * 2 * 2 = 12.56
For a square, the side length is (12.56 / 4 = 3.14) and the area is (3.14 * 3.14 = 9.8596)
So the circle has a large area
A 48 meter long fence is used to form a site on the open space. There are several existing schemes, such as regular triangle, square, regular hexagon and circle. Which site has the largest area
When the perimeter is equal, the area of the round field is the largest
If two rational numbers are added, must the sum be greater than each addend? If two rational numbers are subtracted, must the difference be less than the subtracted? Please give an example
Not necessarily, the addition may be negative, the subtraction may be negative, or 0
2+（-1）=1 2
For example: (1) two numbers are added, and the sum is less than one of the addends and greater than the other; (2) two numbers are subtracted, and the difference is 6, and the difference is greater than the subtracted
(1) For example, if - 2 + 4 = 2, it can be equal to one positive and one negative. (2) 4 - (- 2) = 6, it can be equal to one positive and one negative
If you subtract two numbers, the difference must be less than the subtracted. If you add two numbers together, the sum must be greater than any addend
If two positive numbers are subtracted, the difference must be less than the subtracted; if two positive numbers are added, the sum must be greater than any one of them
RELATED INFORMATIONS
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