When a letter is multiplied by a number and the multiplication sign is omitted, () is usually written before ()

When a letter is multiplied by a number and the multiplication sign is omitted, () is usually written before ()

Alphanumeric

How to read number pairs

The vertical row of a pair of numbers is called a column, and the horizontal row is called a row. To determine which column counts from left to right and which row counts from front to back

A problem about circle in analytic geometry of high school mathematics (urgent)
If the circle passes through points (3,4) and (2,5), the center C is on the line x + Y-8 = 0
(1) Find the equation of a circle
(2) if the line y = KX + 4 is tangent to the circle C, find the distance of the real number K

Let C be (x, y)
y＝8－x
Square of (3-x) + square of (8-x-4) = square of R
Square of (2-x) + square of (8-x-5) = square of R
(PS I haven't touched a high school topic for two months. I forgot a little. Is k evaluation

20 written arithmetic questions of multiplying two digit by three digit in grade four of primary school

The number of real roots of equation 5-x & # 178; = - 1 / X is 1.2.3
The number of real roots of equation 5-x & # 178; = - 1 / X is (additive process)

3

Given the ellipse X & # 178 / 9 + Y & # 178; = 1, find the maximum area of the inscribed rectangle ABCD. (multiple methods)

Let the vertex of the rectangle in the first quadrant be m (x, y), then the area of the rectangle is s = 4xy
Now find the maximum value of S = XY under the condition x ^ 2 / 9 + y ^ 2 / 4 = 1
From the inequality of arithmetic mean and geometric mean, it is obtained that
S=4xy=4*(x/3)*(y/2)*6

Mathematics problems in fourth grade of primary school with brackets

[(3+50)x88+1]x88

Given the function ∫ (x) = A-1 / | x |, if the value range of function y = ∫ (x) on [M, n] is [M, n] (m ≠ n), find the value range of real number a
Above is the third question
concrete:
The known function f (x) = A-1 / | x|
(1) Prove that the function y = f (x) is an increasing function on (0, + ∞)
(2) If f (x)

From F (x) = f (- x), it is even function;
According to the fact that (1) is an increasing function on (0, + ∞), it is a decreasing function on (- ∞, 0)
If 0

Minimum distance from point P to (2.0) on ellipse x ^ 2 / 36 + y ^ 2 / 20 = 1

Let x = 6cost, y = (2 √ 5) Sint. = = > distance d ^ 2 = (2-6cost) ^ 2 + 20 (Sint) ^ 2 = 16 [(cost-0.75) ^ 2] + 15 ≥ 15. The equal sign is obtained only when cost = 0.75. = = = = > Dmin = √ 15

Solving 20 classic simple operation problems

Is it grade 6 or grade 6? 1.45 of 44 * 37 = (1-45 of 1) * 37 = 1 * 37-45 of 1 * 37 = 36 and 45 of 82.1234 + 2341 + 3412 + 4123 = 1 * 1111 + 2 * 1111 + 3 * 1111 + 4 * 1111 (1 + 2 + 3 + 4) * 1111 = 111103.5 of 14 * 23.4 + 11.1 * 57.6 + 6.54 * 28 = 2.8 * 23.4 + 2.8 *