Given the function y = (M + 2) X2 - (4m-1) x-2m, (1) when m takes the value, there are two different intersections between the image and the X axis; (2) when m takes the value, the two intersections are on both sides of the origin

Given the function y = (M + 2) X2 - (4m-1) x-2m, (1) when m takes the value, there are two different intersections between the image and the X axis; (2) when m takes the value, the two intersections are on both sides of the origin

There are two different intersections between the image and the x-axis, that is, the equation (M + 2) X2 - (4m-1) x-2m = 0 has two different real roots m + 2 ≠ 0m ≠ - 2 △ = (4m-1) ^ 2-4 (M + 2) (- 2m) = 16m ^ 2-8m + 1 + 8m ^ 2 + 16m = 24m ^ 2 + 8m + 1 = 24 (M + 1 / 6) ^ 2 + 1 / 3 > 0. For any real number m, △ is greater than 0, so when m ≠ - 2

A mathematics comprehensive practice group from class 2, grade 9 of a school went to Wal Mart supermarket to investigate the sales of a certain commodity during the "October 1" festival. The following is the communication between Xiaoyang and two other students after the investigation: Xiaoyang: according to the investigation, the purchase price of the commodity is 12 yuan / piece. Xiaojia: when the price of the commodity is 20 yuan, 240 pieces can be sold every day. Xiaoxin: on the basis of 20 yuan According to their dialogue, if the goods sold can make a profit of 1920 yuan per day, how should the pricing be more reasonable?

If a and B are real numbers, the equation 3x-5 = bx-a + 1 has a unique solution if

3X-BX=5+1-A
(3-B)X=6-A
X=6-A/(3-B)
The condition is x = 6-A / (3-B) and B is not 3

Junior three mathematics, junior three mathematics, please answer in detail, thank you! (19 12:30:20)
A factory made a profit of 1 million yuan in January and 3.31 million yuan in the first quarter

Suppose the average growth rate is x, then the profit in February is 100 (1 + x), and the profit in March is 100 (1 + x) (1 + x) = 100 (1 + x) & sup2; so 100 + 100 (1 + x) + 100 (1 + x) & sup2; = 3311 + (1 + x) + (1 + x) & sup2; = 3.31x & sup2; + 3x-0.31 = 0 (x-0.1) (x + 3.1) = 0 obviously x > 0, so x = 0.1 = 10% and the average growth rate is 10%