It is known that the solution set of inequality ax ^ 2 + 2aX + 1 > 0 is r··· It is known that the solution set of the inequality ax ^ 2 + 2aX + 1 ＞ 0 is r, and the inequality x ^ 2 + (a + 1) x + a ≤ 0 is solved

It is known that the solution set of inequality ax ^ 2 + 2aX + 1 > 0 is r··· It is known that the solution set of the inequality ax ^ 2 + 2aX + 1 ＞ 0 is r, and the inequality x ^ 2 + (a + 1) x + a ≤ 0 is solved

The solution set of inequality ax ^ 2 + 2aX + 1 > 0 is r,
A = 0 meets the requirement
If a ≠ 0, then the image of y = ax ^ 2 + 2aX + 1 is a parabola,
If the solution set of ax ^ 2 + 2aX + 1 ＞ 0 is r, it needs to open up and the discriminant is less than 0,
That is, a > 0,4a ^ 2-4a

Solving inequality x * x + 1 / 2x (3-2x)

x^2+3/2x-x^2

What is the initial speed and displacement of the car in 10 seconds when the car stops after driving at a constant speed of 2m per second for 10 seconds

The initial velocity is v VT = V + at and finally stops. So VT = 0
v-2m/s*10s=0 v=20
The displacement is calculated by the direct displacement formula
S=V＊t+0.5at^2

Xiaoqiang and Xiaogang collect stamps. After Xiaoqiang gives one fifth of the stamps to Xiaogang, Xiaogang gives one third to Xiaoqiang. At this time, they each have 180 stamps
How many of them were there?

Let Xiaoqiang have X and Xiaogang have y
(1-1/5)X+1/3Y=180
(1-1/3)Y+1/5X=180

English problems in the second semester of junior one
Fill in the blanks according to the meaning of the sentence
1.The problem is re==easy.I think you can do it by _____ .
2.I have a pen pal in Australia.We often _____ to each other.

1 yourself
2 write

The unit length of a certain number axis is 1cm. If a line segment AB with length of 2010cm is drawn randomly on the number axis, how many integer points are covered by the line segment AB?

If you start from an integer point, you can cover: 2010 + 1 = 2011
If you don't start with integer points, you can cover 2010

There are two hats, three coats and three pairs of trousers on the hanger. A suit can be made up of any one hat, one coat and one pair of trousers. How many different kinds of clothes can be made up of at most? (there should be a simple calculation process)

2*3*3＝18

Find seven on the rational number of mixed operations, to process ah, thank you

12—（—18）+（—7）—15
Original formula = 12 + 18 + (- 7) + (- 15)
=（12+18）+〖（—7）+（—15）〗
=30+（—22）
=8

2m3 50m3 decimeter = () M3

2m3 50m3 decimeter = (2.05) M3

The scale is 0, 40, 80, 120 km. On the map, the distance between a and B is 9 cm. A truck and a bus are running towards a and B at the same time, 4 hours
When we meet later, it is known that the speed ratio of the passenger car and the freight car is 5:4. What are the speeds of the passenger car and the freight car respectively? What is the formula

40*9=360
360/4=90
90/9=10
10*5=50
10*4=40
A: 50 km / h for passenger cars and 40 km / h for freight cars