I have a math problem to ask for, please excuse me, OK

Make a cuboid carton out of four identical rectangles and two identical squares of cardboard, its surface area is 266 square decimeters and long. Wide. The length of the height is the whole decimeter, and the volume of the carton is as large as possible, what is the volume of this carton?

Suppose the rectangle is long y and wide x, and the square is long and wide y

The volume of this carton is equal to XY 2

2(2xy+y^2)=266

2xy+y^2=133

y(2x+y)=7*19

So. y=7

2x+y=19

x=6 so the maximum volume of the carton is.

294 cubic decimeters.

If one side of the square is x, then one side of the rectangle is also x, and if the other side is y, then there is. 2x^2+4x*y=266

x^2+2xy=133

x^2+2xy

x^2+xy+xy

3 times 3 times under the root sign (x 2*xy*xy) = 3 * 3 times under the root sign [(x*x*y) 2] (if and only if x 2=xy=xy, the equal sign holds, i.e., x=y).

That is, 266>=3*3 times root number [(x*x*y) 2] and v=x*x*y

So 3*3 times root number under [v 2] = <266

v^2=<(266/3)^3

The maximum v can be obtained.

Write exponential as logarithmic, which is the value of x. That is, the logarithm of 7 with 5 as the base.

x=1og with 5 as the base 7 logarithm Write x=1og5 7 x approx.

(1) 5 parts of 6x12=

2) 3 parts of 8x40 = 3 5

3) The sum of 5 3/10 = of the sum of 3 out of 10

4) 3 times 3 times of 8 =

5) On the eve of the Spring Festival, Xiao Ming's father wants to make a cube lantern with an edge length of 20/9 meters, and the frame should be thick wire = 9 20 12 = meters.

6) It takes 2 minutes for a steel pipe to be sawn into 2 sections.

If sawn into 4 sections = 2 5 3 = minutes.

7) 9 out of 14 x 7 out of 18 = 1 4

8) 12 out of 16 x 12 out of 25 = 9 25 (9) A marketer takes a train from city A to city B. Halfway through the train, the salesman fell asleep. He woke up and looked at the road signs and found that the remaining distance was 3 parts 1 of the train he had traveled before he fell asleep.

At this time, the train traveled the whole journey of =1-(1 2 1 3)=5 6(1)5x4 + 5 parts 2x2 + 5 parts 1x16=4 5 (4+1+4).

2) 2009x2009 of 2010

2008 and 1 2010