If two of the equations (lgx) ^ 2 + (lg7 + lg5) * lgx + lg5 * lg7 = 0 are n, m, then Mn =? If two of the equations (lgx) ^ 2 + (lg7 + lg5) * lgx + lg5 * lg7 = 0 are n, m, then Mn =? Process, thank you~

If two of the equations (lgx) ^ 2 + (lg7 + lg5) * lgx + lg5 * lg7 = 0 are n, m, then Mn =? If two of the equations (lgx) ^ 2 + (lg7 + lg5) * lgx + lg5 * lg7 = 0 are n, m, then Mn =? Process, thank you~

From the root formula of quadratic equation of one variable,
lg(mn)
=lgm+lgn
=-b/a
=(lg7+lg5)
=lg(1/35)
mn=1/35

At the "welcome the Olympic Games, I'm the first" get-together, the monitor prepared several identical cards, which were written with the questions to be answered by the students at the get-together.after the get-together, the monitor asked Xiao Ming: can you design a plan to estimate how many cards were prepared for the get-together.xiao Ming used 20 blank cards (the same as the cards with questions), and washed all the cards with questions 10 of them were randomly selected, and two blank cards were found. The number of the problem cards was correctly estimated immediately. Xiaoming estimated that the number was ()
A. 60 B. 80 C. 90 D. 110

20 △ 210 = 100 (sheet), 100-20 = 80 (sheet)

If f (x) = a | X-B | is a decreasing function on (2, + ∞), what conditions should a and B satisfy?

Because the function f (x) = a | X-B | is a decreasing function on (2, + ∞), a is not equal to 0, and this function is a linear function
1. If x > b, then f (x) = ax ab
So ab
Then f (x) = ax AB, so a

Make a 256 cubic meter square bottom water tank without cover______ Rice is the most economical time

Let the height of the tank be x, and the length of the bottom edge be a, then a2x = 256, and its surface area s = 4ax + A2 = 1024a + A2 = 512a + 512a + A2 ≥ 3 × 26 = 192. If and only if a = 8, that is, H = 25682 = 4, then s gets the minimum value

Plane vector triangle
In the triangle ABC, the midpoint m is the midpoint of BC. Prove: vector AB + vector AC = 2 vector am

Vector AB + vector AC
=(vector AB + vector BM) + (vector AC vector BM)
=Vector am + (vector AC vector MC)
=Vector am + (vector AC + vector cm)
=Vector am + vector am
=2 vector am

Let a = {1, x, LG (XY)}

If k = LG (XY), then the K power of 10 is XY
Maybe that's better

The teacher arranged the same amount of oral arithmetic exercises, the time and speed of doing oral arithmetic

Inverse proportion
If you don't understand, you can ask

If x = 1 and y = 2 are the solutions of the equations ax-t = B 3ax + by = 6, then what are the values of a and B? What are the common solutions of the equations y = 2x-3 and 3x + 2Y = 1?
A movie ticket is 20 yuan per ticket, B movie ticket is 15 yuan per ticket. If you buy 40 movie tickets of a and B, and it costs 700 yuan, how many movie tickets of a?

Suppose a bought x, B bought 40-x
20X+15（40-X）=700
5X=100
X=20

Use 1, 3, 5, 7, 9 to form a formula of three digit times two digit product (each digit can only be used once), and calculate the result

According to the nature of multiplication formula and digital knowledge, we can use 1, 3, 5, 7, 9 to form the multiplication formula of three digit by two digit. The largest formula of multiplication is: 751 × 93 = 69843

Why is the slope of a straight line intersecting a hyperbola less than that of an asymptote

First of all, what you said is not strict. That's why you asked this question. I think what you asked is a straight line passing through the origin of coordinates. Only when the slope of a straight line passing through the origin of coordinates is less than the slope of the asymptote, can it have an intersection with the hyperbola. At this time, the reason is that the definition of hyperbolic asymptote has one meaning of asymptote: self variation