If a + B = a quarter and A-B = a half, what is the square of A-B?

Square of a - square of B = (a + b) (a-b) = 1 / 4 x 1 / 2 = 1 / 8

(0.125) ^ 2008 times (- 1 / 4) ^ 100 times 4 ^ 99 times 8 ^ 2009

Its formula is as follows:
（0.125）^2008X（-1/4）^100X4^99X8^2009
=（0.125）^2008X8^2009X（-1/4）^100X4^99
=(0.125X8)^2008X8X(1/4）^100X4^99
=1^2008X8X(1/4X4)^99X1/4
=8X1^99X1/4
=8X1/4
=2

How to calculate 1999 * 2009.2009-2008 * 1999.1999

1999*2009.2009-2008*1999.1999
=1999x2009x1.0001-2008x1999x1.0001
=1999x1.0001x（2009-2008）
=1999.1999

In 1990, 1992, 1996, 1998, 2000 and 2008, the year of leap year is ()

In 1992, 1996, 2000 and 2008, as long as you divide by four, you can divide it completely

20.903 is equal to how many times ten plus how many times nine plus how many times three

2×10+0.1×9+0.001×3

Xiaoming and Xiaogang start from a to B at the same time. Xiaoming's speed is 8 kilometers per hour and Xiaogang's speed is 6 kilometers per hour. In 20 hours, Xiaogang is overtaken by Xiaoming for the second time. How long is the distance between the two places?

The idea upstairs is right, but the title says catching up for the second time. Then, Xiao Ming should have run two more rounds than Xiao Gang
Distance between the two places = (20 * 8-20 * 6) / 4 = 10km

It's not too much to translate English phrases

can't be too...

Using paper-cut scissors to cut objects, is it easy to use the tip of scissors or the middle of scissors to cut objects

It depends on what you cut. The thin one uses the tip and the thick one uses the middle

When a cuboid 8 cm long, 6 cm wide and 4 cm high is cut into two cuboids, the sum of the surface areas of the two cuboids can be increased by () square percent at most
rice

Zifeiai,
Maximum increase: 8 × 6 × 2 = 96 (square centimeter)
Minimum increase: 6 × 4 × 2 = 48 (cm2)

0 7 （） 18 （）（）（）
Who knows if this problem is wrong?
18 is three separate numbers

0 7 （13 ） 18 （22 ）（25 ）（27 ）
0＋7＝7
7＋6＝13
13＋5＝18
18＋4＝22
22＋3＝25
25＋2＝27

If a + B = a quarter and A-B = a half, what is the square of A-B?