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1.There are x defective products.

Then the probability of drawing 2 pieces to the defective product is.

c(x,2) x*(x-1)p = --= --=c(100,2) 100*99 x 2 - x - 99 <=0

Solve x<=

Therefore, there are a maximum of 10 defective products in this batch of products.

2.a oxidation capacity is related to the ability of electrons, and has nothing to do with the number of electrons3This is exempt, it's inconvenient to draw.

Welcome to the [Middle School Mathematics, Physics and Chemistry Answers] group questions and exchanges.

1.Tie a heavy object on the balloon, the air laughing eggplant destroys the ball with the weight at a constant speed of 4m s, when the rope is suddenly broken when it is 9m off the ground, try to find: (1) the height that the weight can rise after leaving the balloon (2) how much time it takes from the rope break to the weight landing.

Answer: (1) (2).

2.It is known that a={x|k+1<=x<=2｝，b=｛x|1<=x<=3}, a really contains b, and the range of values of the real number k is prepared.

Answer: k<=3 2

3.The value of Avogadro's constant is expressed by na, and the following statement is correct ()aUnder standard conditions, 1 L of water contains 1 b

Under normal conditions, the number of molecules in the solution is the number of molecules containing Cl- and the number of electrons lost in the reaction with sufficient amounts of dilute sulfuric acid and sodium hydroxide is Na3Na

Answer: d

At (-00,0),(0,+00), monotonically decreasing, no increase interval.

2.Proof: Set x1 x2

then f(x2)-f(x1)=x2 + 1 x2 -x1 - 1 x1=(x2-x1)- x2-x1) x1x2 =(x2-x1)(1-1 x1x2).

When 0 x1x2 = 1 is a monotonically decreasing function. Use the definition method.

3.If there is a problem with the problem, f(1-a)+f(1-a) 2=f(1-a)[1-f(1-a)]<0, get -14Or use the definition method to destroy with caution, note that x 3 is an incremental function on r, and do not need to be clear.

Question 4 can be obtained directly with the derivative.

The first question doesn't need to be asked in large size, junior high school classmates!

The second question is x 2+1 x, and then ··

The third question is even simpler.

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1. The inverse proportional function decreases monotonically when k 0, and there is no increase interval at all.

2. Let x1 and x2

Then f(x2)-f(x1)=x2 + 1 is good x2 -x1 - 1 x1=(x2-x1)- x2-x1) x1x2 =(x2-x1)(1-1 x1x2) when 0 x1x2 1 is a monotonous decreasing lead function.

I don't want to fight. I would like to ask you are sure that there is no problem with the question?

Prove it with definitions, step by step, it's simple.

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1,: When discussing 2m-1=-3, 2m+9=5, change the verification value of the previous m.

2<=m<=-1

2: This is a standard question for physics, S 2 is not the same as T 2.

3: O2 and O3 still ask?