Whose square is 144? Is - 12

Whose square is 144? Is - 12

It's the square of ± 12

What's the rule of the two numbers at the end of a five digit square? Why?

The two digit number is 10N + 5, where n = 1,2,3,4,5,6,7,8,9
(10n+5)^2=100n^2+25+100n=100(n^2+1)+25
So the last two numbers are both 25

How to calculate the area of ellipse?
There seems to be no formula in my memory

Pai * AB, a, B are semi major and minor axes respectively
The proof needs calculus knowledge or advanced geometry proof

Sixth grade first volume mathematics exercise book (Shanghai Education Press) page 14 answer! Continue

10. 5 / 12, 7 / 12, 11 / 12, 13 / 12, 17 / 12
11. Whatever
12. Whatever
two point three
The least common multiple of 1.3 and 24 is 23
.
Because 16 out of 24 is more than 5 out of 24, 2 / 3 is more than 5 out of 24
The least common multiple of 2.18 and 21 is 126
.
Because 78 out of 126 is greater than 77 out of 126, 13 out of 21 is greater than 11 out of 18

Let α and β be the two real roots of the equation x square - (2m + 1) x + m square + 1 = 0, and find the minimum value of α square + β square

Discriminant ≥ 0
(2m+1)^2 - 4(m^2+1) ≥0
4m-3≥0
m≥3/4
α. β is the two real roots of the equation x square - (2m + 1) x + m square + 1 = 0
According to Weida's theorem:
α+β = 2m+1
αβ = m^2+1
α^2+β^2 = (α+β)^2-2αβ = (2m+1)^2 - 2(m^2+1) = 2m^2+4m-1=2(m+1)^2-3
When m ＞ - 1, α ^ 2 + β ^ 2 = 2 (M + 1) ^ 2-3 increases monotonically
m≥3/4
The minimum value of α ^ 2 + β ^ 2 = 2 (3 / 4 + 1) ^ 2-3 = 2 * (7 / 4) ^ 2-3 = 25 / 8

Grade 5 Volume 1 mathematics academic assessment page 22 question 8
When calculating the division with remainder, Maomao writes the divisor 113 as 131. The quotient is 3 more than the original, but the remainder is exactly the same. What is the remainder?

Because the remainder is the same and the quotient is more than 3
Let the divisor be X
Then 131-113 = 3x
The solution is x = 6
113 divided by 6 = 18
131 divided by 6 = 21 more than 5
Then the remainder is 5

It is known that circle C1: x ^ 2 + y ^ 2 + 2x + 2y-8 = 0 intersects circle C2: x ^ 2 + y ^ 2-2x + 10y-24 = 0 at two points a and B. find the linear equation and common chord length of common chord AB (find the explanation and explain how to do it)

(1) C1: x ^ 2 + y ^ 2 + 2x + 2y-8 = 0c2: x ^ 2 + y ^ 2-2x + 10y-24 = 0. Because a and B are the common points of C1 and C2, C1-C2 obtains the linear equation x-2y + 4 = 0 (2) of common string ab. substituting the above formula into C1, the solution is Y1 = 0, y2 = 2, corresponding to X1 = - 4, X2 = 0, so the coordinates of a and B are a (- 4,0), B (0,2) common

Answers to the fourth grade mental arithmetic question cards

Why do you always want the answers on the answer sheet? Oral arithmetic needs to be practiced every day. There are many free oral arithmetic websites on the Internet. You can search it on Baidu. It's OK to search oral arithmetic and oral arithmetic websites. The fourth grade's oral arithmetic will automatically set questions and correct them. All the wrong questions will be displayed to you. You don't need to find the answers at all

How many square decimeters is the area of a square surrounded by 2.96 meters long wire?

Square side length = 2.96 △ 4 = 0.74 (m) = 7.4 (decimeter)
Area of square = 7.4 × 7.4 = 54.76 (square decimeter)
A: the area of this square is 54.76 square decimeters

For a simple harmonic vibration object, the acceleration value is the largest at a certain time. When the object passes through s distance, the velocity value is the largest, and its amplitude may be?
The answer is s / (2k + 1) why

You should say that the distance you pass is s. at a certain moment, the acceleration is the maximum, which means that the object is at the farthest end. After passing through s, the speed reaches the maximum, which means that the object is at the lowest point. When k = 0, the object just completes 1 / 4 cycle,
So its amplitude is s. when k = 1, the object goes through one cycle, another half cycle and then reaches the lowest point. So the amplitude should be s / 3, and so on. 2K + 1 refers to the number of cycles