What is an imaginary number? Is the square root of a negative real number an imaginary number? Some people say that negative numbers have no square root. Others say that the square root of negative numbers is imaginary. Which one is right?

Most people are familiar with two kinds of numbers, positive number (+ 5, + 17.5) and negative number (- 5, - 17.5). Negative number appeared in the middle ages, which was used to deal with the problem of 3-5. From the ancient people's point of view, it seems impossible to subtract five apples from three apples. However, the merchants in the middle ages have clearly

RELATED INFORMATIONS

1. The square root of an imaginary number is still an imaginary number. What's wrong?
2. The roots of imaginary numbers for solving equations -5x square + 8x-5
3. If the intersection of the line y = K (x-1) + 1 and the circle x ^ 2 + y ^ 2-4x-12 = 0 is in the third quadrant, then the value range of the real number k is? Yes?
4. As shown in the figure, the center of the small circle is at the origin, the radius is 3, the center coordinates of the big circle are (a, 0) and the radius is 5. If there are two circles, then the value range of a is______ ．
5. The equation of a circle whose center is at the origin and whose circumference is divided into 1:2 parts by a straight line 3x + 4Y + 15 = 0 is______ ．
6. If the origin is outside the circle x ^ 2 + y ^ 2 + 2x + 4y-a = 0, then the value range of a is 0
7. If the distance between any point on the circle (x-1) ^ 2 + (Y-1) ^ 2 = R ^ 2 (r > 0) and the origin is 1, the value range of R can be obtained
8. The minimum value of function y = (SiN x) ^ 4 + (COS x) ^ 2, X ∈ [0,6 / π] is -——
9. Find the maximum and minimum of the function y = sin (x + π / 6) + cosx, (0 ≤ x ≤ π)
10. Known K
11. Thank you so much for telling me the meaning of imaginary root
12. It is known that the set a = {a} has a unique real solution to the equation x & # 178; - 2 / 2 x + a = 1 of X}, and the set a is represented by enumeration
13. Is it possible for the roots of a quadratic equation of one variable of complex number to be a real number and an imaginary number? I just learned plural. I hope you can take care of me!
14. What are real numbers and imaginary numbers?
15. Does the equation of imaginary number have a real root and an imaginary root?
16. How to find the root of imaginary number and the number of roots of higher order equation? For example, if x ^ 3-4x ^ 2-3x + 2 = 0, how can we know that it has several imaginary solutions and several real solutions?
17. Help me look at some math problems! It's a process (2xy-y) - (- y + YX) =? 5 (a squared b-3ab squared) - 2 (a squared b-7ab squared) =? First simplify, then evaluate (4a + 3a square-3 + 3A cube) - (- A + 4A cube), where a = - 2: 1 2X squared y-2xy squared - [(- 3x squared y squared + 3x squared y) + (3x squared y squared - 3xy squared)] Where x = - 1, y = 2
18. In the quadrilateral ABCD, EF divides AB into three equal parts and Mn divides DC into three equal parts
19. The taxi charge standard of a city is: the starting price is 3 km 5 yuan, more than 3 km, 1 km plus 1 yuan during the day; after 10 pm, 1.2 yuan per km At 22:15, Aunt Wang took a taxi to the fire station for a total of 7.8 kilometers. How much should Aunt Wang pay?
20. If the quadrilateral ABCD is a square and the triangle EBC is an equilateral triangle, then the degree of angle X is () degrees