(- 2 radical 2) square - (radical 2 + 1) square + (radical 2-1) negative power Please help me

(- 2 radical 2) square - (radical 2 + 1) square + (radical 2-1) negative power Please help me

(-2√2）^2-（√2+1）^2+(√2-1)^(-1)
=8-3-2√2+√2+1
=6-√2

If we know that the - 2 power of X + the 2 power of x = 2 times the root 2 and x > 1, then the square of X - the - 2 power of X?

(x^-2+x^2)^2=(2√2)^2
x^-4+2+x^4=8
x^-4+x^4=6
(x^2-x^-2)^2
=x^4-2+x^-4
=6-2
=4
x>1
So 00
So x ^ 2 > x ^ - 2
So x ^ 2-x ^ - 2 > 0
So x ^ 2-x ^ - 2 = 2

The simple method is used to calculate 2011 of 2012 × 2013, and the simple method is used to calculate 50 and 2 × 24 of 11

2012x2011/2013
=（2013-1）x2011/2013
=2013x2011/2013-2011/2013
=2011-2011/2013
=2010 and 2 / 2013

25 (x + y) quadratic-16 (X-Y) quadratic
X quadratic - 4Y quadratic + X + 2Y
(x + 2) (x + 4) + X quadratic-4

25 (x + y) quadratic - 16 (X-Y) quadratic = [5 (x + y)] &# 178; - [4 (X-Y)] &# 178; = (5x + 5Y) &# 178; - (4x-4y) &# 178; = (5x + 5Y + 4x-4y) (5x + 5y-4x + 4Y) = (9x + y) (x + 9y) x quadratic - 4Y quadratic + X + 2Y = (x + 2Y) (x-2y) + (x + 2Y) = (x + 2Y) (x-2y + 1) (x + 2) (x + 4) + X

The speed ratio of passenger and freight cars is 4:3. When the two cars meet, the number of passenger cars decreases by 20%, and the speed of freight cars increases by 1 / 3,
The truck is 25 kilometers away from a, so the speed of the two places should be calculated
No equations

When they met, there were three for the bus and four for the truck
The later speed of the bus was 4 × (1-20%) = 3.2 phr
The later speed of the truck was 3 × (1 + 1 / 3) = 4 parts
When the passenger car finished the remaining three parts of the journey, the freight car did 3 △ 3.2 × 4 = 15 / 4
There are still 4-15 / 4 = 1 / 4 parts left in the truck
The distance of each piece is 25 △ 1 / 4 = 100 km
The distance between the two places is 100 × (3 + 4) = 700 km

Hello, I want you to calculate for me. The thickness of the plate is 0.53mm, 406 color steel plate. There are 5148 square meters in total. Help me calculate how many tons of color steel plate I need
There are also calculation methods, please write down. Let me calculate other materials. How many small tons ~ ~ thank you

The density of color steel plate is about 7.82-7,83
5148 × 7,82 × 0,53 △ 1000 = 213637 tons

With a batch of cement, team a can transport it in 10 days, team B can transport it in 15 days, and team C can transport it in 20 days
Team a left in the middle of the three teams' joint games, which took six days to complete. How many days did team a actually transport

In six days
Team B finished two fifths
Team C 3 / 10
So team a finished 3 / 10
So team a works for three days

The volume sum of cone and cylinder with equal base and height is 12.56 cubic decimeter, and the volume of cone is () cubic decimeter
A. 3.14B. 6.28C. 12.56D. 25.12

A: the volume of a cone is 3.14 cubic decimeter

A number is not only a factor of 63, but also a multiple of 9. The minimum number is () and the maximum number is ()
Urgent! 1

63 itself can be divided by 63 by 1,3,7,9,63. At the same time, it is a multiple of 9, 9,63. Among these, the largest is 63 and the smallest is 9

It is known that a = 3b to the power of 2-2a + 5ab, B = 4ab-2b to the power of 2-a
Where a = 2, B = - 3, find the value of 2 (3a + b) - 3 (5b-a) + 4 (2b-3b)

(1) A=3b^2-2a^2+5ab ,B=4ab-2b^2-a^2
(2) A=(3b)^2-(2a)^2+5ab ,B=4ab-(2b)^2-a^2
2（3A+B）-3（5B-A）+4（2B-3B）=6A+2B-15B+3A-4B=9A-17B
(1) If a = 2, B = - 3, a = - 11, B = - 46
Original formula = 9a-17b = 683
(2) If a = 2, B = - 3, a = 35, B = - 64
Original formula = 9a-17b = 1403