Help to do this problem, to be specific to the problem solving process, to be detailed

The answer should be September 1.

Xiao Ming said: If I don't know, Xiao Qiang definitely doesn't know that Xiao Ming knows the month, if the month he knows is 6 or 12, he can't say the above words so sure, so June and December are excluded, and March and September are left.

Xiaoqiang said: I didn't know it at first, but now I know.

Xiaoqiang knows the date, but because Xiao Ming said "If I don't know, Xiaoqiang definitely doesn't know", after Xiaoqiang excluded June and December, Xiaoqiang knew, indicating that the day Xiaoqiang knew was definitely not the 5th, but March 4th, March 8th, and September 1st.

Xiao Ming said: Oh, then I know too.

Since Xiao Qiang said, "I didn't know it originally, but now I know", after Xiao Ming excluded the 5th, Xiao Ming knew, then the month that Xiao Ming knew was definitely not March (if it was March, Xiao Ming didn't know if it was the 4th or the 8th), it could only be September, and the answer came out: September 1st.

On September 1, Xiao Ming said: "If I don't know, Xiao Qiang definitely doesn't know."

From this sentence it is possible to exclude the month. Because they have a single number.

Only March. September.

Xiaoqiang said: I didn't know it at first, but now I know.

From this sentence it is possible to exclude the same mantissa 5...And also.

Xiao Ming said: Oh, then I know too.

From this sentence, it can be known that the birthday is.

You take the square.

Overlap point O and point A.

Then the obvious answer is d.

Suppose you want to prove the process in detail.

Give an adoption. I'll write to you later.

If you want to do it openly, it is a completely general situation. But there are clever tricks to such problems, for example, you can put point O at A, choose D, 4om

o Point to take it casually is this principle.

<> back to the two escorts to answer the slippery reed wax analogy with this.

A 2-A 2sin 2(t) = A 2(1-Sin 2(t) 晌 dry coarse) = A 2cos 2(t).

The banquet town in the back is similar to this kind of practice.

1) Define the domain:

3-x)/(3+x)>0

3-x)/(3+x)>0

x-3)(x+3)<0

x-3)/(x+3)+(x+3)/(x+3)≤0∴2x/(x+3)≤0

x(x+3) 0 and x+3≠0

3 So the set of solutions to the sought inequality is (-3,0).

3) Define the domain (-3,3) with respect to the origin symmetry, and f(-x)=lg(3+x) (3-x)=lg[(3-x) (3+x)] 1)=-lg(3-x) (3+x)=-f(x), so the function is odd.

Expand the top and bottom and write as:

Top: A 3*N 100+P1*N 99+P2*N 98+......p100

Bottom: n 100 + Q1 * N 99 + Q2 * N 98 + ......Q100 is divided by n 100 up and down, because n, except for the first term, each subsequent item has 0, and the number is limited.

So the upper equation and the lower equation = a 3 1 = a 3 = 8a = 2

dy=π^x lnπ +x^（x-1）dx

Differentiation is dy=y'Dress up as a fierce DX

What else do you need to cross the wide family journey, only the hall Qiaoqiao has one step to seek guidance.

It's obviously a math problem, right?9 points 2 1km

d(lnx)²=2lnx/x dx

Multiply the past to about one x and become x lnx

It should be that there is a problem here, you can do the math.