Science Mathematics Advanced Junior 1 Science 10

1.Weigh the mass of the large beaker m1 with a balance

2.Place a small beaker filled with water into the large beaker and tie the metal block with a thin wire so that it completely submerges into the water of the small beaker, and the water in the small beaker overflows into the large beaker.

3.Take out the metal block and the small beaker and re-weigh the mass of the large baked cake with water m24With m2-m1, the mass of the obtained and overflowed water, and the density is divided by this mass (the volume of 1 gram of water is 1 cubic centimeter), and the resulting volume is the required volume of the metal block.

Another: The supplementary question is not very clear, hehe.

1. Weigh out the mass m1 of the empty beaker

2. Carefully put the small beaker into the large beaker, and be careful not to spill water into the large beaker.

3. Tie the block with a thin line, and carefully immerse the block in the water with the thin line, pay attention here as long as the block is just immersed in the water, do not put it into the water at once, because the thin line also has volume!

4. Take the small beaker out of the large beaker.

5. Weigh the mass of the large beaker m2

6. (m2-m1)*1 block volume.

Wrap a copper wire around a pencil 50 times, and measure the length of the coil with a scale, then the diameter of the copper wire is (cm), and the minimum scale of the scale used is (8 cm).

Measure the total mass of a small beaker filled with water and mark m1

After the small metal block is completely immersed, take it out, measure the mass of the remaining water and the small beaker, and remember that the volume of the small metal block m2 is (m1-m2) 1g cm3 The diameter of a copper wire is 1nm.

The minimum scale of a general scale is 1mm

The diameter of a copper wire is 1nm, right? The minimum scale we use is 1mm

Solution: 2009 and 2010/2009 can be written as a system:

2009*2010+2009) 2010 is (2009*2011) 20102009 divided by 2009 and 2009/2010, i.e. the reciprocal of 2009* (2009 and 2010/2010) that is:

That is: 2010/2011

Solution: If the investment in project A is 10,000 yuan, the investment in project B is (20-x) yuan.

A x = 15 B 20-x = 20-15 = 50,000 yuan.

。。。Wouldn't it be nice to solve the equation with two formulas in columns, x+y=200000

Assuming that the investment in project A is x0,000, then the investment in project B is (20-x) yuan.

The revenue of Project A is: x*

Project B's revenue is: (20-x)*

The benefits obtained by this enterprise are: the income of project A + the income of project B.

That is: x* solution gets x*

Project A invests 150,000 yuan and Project B invests 50,000 yuan.

It seems to be a problem of chickens and rabbits in the same cage.

Solution: The project has invested yuan.

Project B invested (200,000) yuan.

Solution: =150,000 RMB.

Project A invested 150,000 yuan.

Project B invested $50,000.

If the landlord learns a quadratic equation, you can.

Solution: The project has invested yuan.

Project B invested $y.

y=200，000

Solution: { 150,000. }

y=50，000

Project A invested 150,000 yuan.

Project B invested $50,000.

First of all, let me explain my understanding of your topic, which means that:

x 4*y n-2x 3 and -1 3 *x 5-4y+1 5 are of equal magnitude, where x 4 is the fourth power of x and * is multiplication.

If I'm not mistaken, please see the answer.

The order of the polynomial is determined by the number of the monomial that makes up the highest order of the polynomial, now the order of the first polynomial is obviously 4+n, the order of the second polynomial is 5, the order of the two polynomials is equal, then n+4=5, then n=1

So n-2n+3n-4n+5n-6n....99n-100n=(1-2)+(3-4)+(5-6)+(7-8)+.99-100)=-1*50=-50 (since you have been exposed to the multiplication and division of integers, you must have learned rational numbers, and the concept of negative numbers should also be established).

The 4th power of polynomial x, the nth power of y, the power of 2x, the 3rd power of polynomial, the same number of times as the 5th power of polynomial-3 branch 1x - 4y + 5 branch 1.

The number of times depends on the highest term, and the number of times that follows the polynomial -3 branch 1x to the power of 5 -4y+5 branch 1 is five.

So we get n=1 original formula = 1-2+3-4+5-6 ......So the original = -50

The second polynomial has a degree of 5, so the first term has a degree of 5 as well

So n=5-4=1

n-2n)+(3n-4n)+(5n-6n)..99n-100n) every two groups, a total of 100 2 = 50 groups, the result of each group is -n, so the original formula = -50n = -50

a|=2,b=-3,c is the largest negative integer.

So a=2 or x=-2

c=-1, so a+b-c=2-3+1=0

or a+b-c=-2-3+1=-4

a-2|=3,|b-3|=4,|c|=2

So a-2=3 a=5

or a-2=-3 a=-1

b-3=4 b=7

or b-3=-4 b=-1

c=2 or c=-2

Because a, b have different signs, and a, c have the same sign.

So a=5 b=-1 c=2

or a=-1 b=7 c=-2

So a-b+c=5-(-1)+2=8

or a-b+c=(-1)-7-2=-10

a) If|a|=2,b=-3,c is the largest negative integer, find the value of a+b-c.

a|=2, so a = 2

b=-3,c=-1

So a+b-c=a+(-3)-(1)=a-2=0 or -4

b) Known: |a-2|=3,|b-3|=4,|c|=2, and a, b with different signs, a, c with the same sign, find the value of a-b+c.

a-2=±3，b-3=±4，c=±2

a = 5 or -1, b = 7 or -1, c = 2 or -2

If a=5, then b=-1, c=2, then a-b+c=8, if a=-1, then b=7, c=-2, then a-b+c=-10

The largest negative integer is -1, and a has two cases, a=2 or a=-2, so a+b-c=0 or -4

The second question is also about the relationship between positive and negative signs.

a=5 or a=-1

b = 7 or -1

c = 2 or -2

And because a, b have different signs, and a, c have the same sign, so they exist.

Case 1 a=5, c=2, b=-1 results in 8, case 2 a=-1, c=-2, b=7 results in -10

Both of the questions you asked need to be discussed on a case-by-case basis.

a): when a=2, a+b-c=2+(-3)-(1)=0 when a=-2, a+b-c=-2+(-3)-(1)=-4 two): a-2|=3, then a = 5 or -1

b-3|=4, then b = 7 or -1

c|=2, then c = 2 or -2

It is also a and b with different names, and a and c with the same name.

It can be seen that when a=5 b=-1 c=2, a-b+c=5+1+2=8, when a=-1 b=7 c=-2, a-b+c=-1-7-2=-10

1.When a=-2, a+b+c=-4

When a=2, a+b+c=0

2.When a=5, a-b+c=8

When a=-1, a-b+c=4

Mathematics: = 28 251 + 28 223 223 28 + 223 251 + 251 28 251 223

12. 1/8x+1=

1/8x - 2x =

15/8x=-

x=16/25

Science: Figure representation: 6*1 0*So the water representation is: 256

256-244 12 (sq.m.).

Mathematics adds:

Define a*b=|a|+|b|, then [1*(-2)*(3)] = solution: because the definition a*b=|a|+|b｜

So 1*(-2) |1|+|2|=1+2=33*（-3）=|3|+|3|=3+3=6, i.e. 1*(-2)*(3)=6

Mathematics 1: 28 251 + 28 223-223 28 + 223 251 + 251 28-251 223 and then merge with the same denominator to get 28 28-223 223 + 251 251 = 1 So the answer to the first question in mathematics is 1

In the second problem of mathematics, we get 1·2=15 8x by moving the term first, so there is 96 80=15 8x, so the solution gets x=

Mathematics supplementary questions [1*(-2)*(3)]=1+[(2)*(3)]=1+2+3=6.

Sorry for the science, I don't know how to read water meters.

200 eggs is 100 pairs.

It is equivalent to 1 pair of salmon becoming 100 pairs in 1 year, that is, 1*10 2 pairs.

Then 2 years becomes 1*10 4 pairs.

3 years becomes 1*10 6 pairs.

And so on. In 13 years, it becomes 1*10 26 pairs.

Is there a requirement for science and technology to keep a few significant figures?

If not, it's 1*10 26 pairs.

Hope it helps

Analysis: When the number of trapezoids is 1, the perimeter is 5a, when the number of trapezoids is 2, the perimeter is 5a+3a, when the number of trapezoids is 3, the perimeter is 5a+2 3a....From this, the circumference of the figure can be obtained when the number of trapezoids is n

Answer: Solution: When n=1, the perimeter of the graph is 5a;

When n=2, the circumference of the graph is 5a+3a;

When n=3, the circumference of the graph is 5a+2 3a;

When the number of trapezoids is n, the circumference of the figure is 5a+(n-1) 3a=3an+2a

So the answer is: 3an+2a

1 2 3 4 5 6 7 8 9 ……36

5a 8a 11a 14a 17a 20a ……Equal difference series up to the 36th number.

The nth is 3an+2a

Because you can take it apart and look at it.

Don't look left and right first, look at the bottom and bottom first.

Add 3a for each additional one

Looking left and right, it's always 2a

So it's 3an+2a

- - Honey, go ask the math teacher.

a-b)^2=a^2+b^2-2ab

b-c)^2=b^2+c^2-2bc

c-a)^2=a^2+c^2-2ac

a-b)^2+(b-c)^2+(c-a)^2=(a^2+b^2-2ab)+(b^2+c^2-2bc)+(a^2+c^2-2ac)

a^2+b^2+c^2-ab-bc-ac

1 2[(a-b) 2+(b-c) 2+(c-a) 2]=1 2[(-1) 2+(-1) 2+2 2]=3I hope it can help you, I wish you progress in your studies!

The square of a + the square of b + the square of c - ab-bc-ca=