Mathematics, solution of linear equation with one variable Since January 1, 2006, a city has implemented the rural cooperative medical system in an all-round way. Every farmer can enjoy the cooperative medical system with only 10 yuan each year. The following table shows the reimbursement rate of hospitalization expenses after the implementation of the rural cooperative medical system Reimbursement rate of hospitalization expenses (yuan) (%) The part not exceeding 3000 yuan 3000-4000 25 4000-5000 30 5000-10000 35 10000-20000 40 Over 20000 45 How many yuan did a person actually bear when he was hospitalized and reimbursed 805 yuan?

3000 * 15% = 450 yuan
1000 * 25% = 250 yuan
100 * 30% = 300 yuan
450+250

A car travels 167 km in 2 hours and a big car 250 km in 3 hours. What are the speeds of the car and the big car?
We should use the knowledge of fraction to solve it!

Car speed = 167 △ 2 = 83 + 1 / 2
Big car speed = 250 △ 3 = 83 + 1 / 3
1/2>1/3
The car is fast

So 3528a is the square of natural number B. what is the minimum value of a?

3528=2*2*2*3*3*7*7=2^3*3^2*7^2
A min 2
3528 * 2 = 7056 = 84 square

The first problem of Mathematics for liberal arts is that the imaginary part of complex number 1 + I / 1-I (I is an imaginary unit) is
Which volume is A-1 B0 C1 D2

Choose C, 1
If the numerator and denominator are multiplied by (1 + I), the denominator becomes (1-I Square) = 2;
The molecule becomes (1 + 2I + I Square) = 2I
So choose C

The ticket price of a scenic spot is as follows: 50 people, 12 yuan per person, 51 ~ 100 people, 10 yuan per person, more than 100 people, 8 yuan per person
There are 102 students from class 1 and class 2 of Grade 7 in a school. There are less than 50 students in class 1 and more than 50 students in class 2. If the two classes buy tickets separately, they will pay 1118 yuan. If the two classes buy tickets together for a group, they can save a lot of money?

There are 49 people in the first class and 53 people in the second class. It costs 816 yuan to buy tickets jointly for the two classes. It saves 302 yuan. Over

Let f (x) be derivable at point X and ab = 0, then Lim Δ x is close to 0, and then (f (x + a Δ x) - f (X-B Δ x) / Δ x can be obtained=

Well, if AB is not equal to, I know how to do it. It's stuck on AB = 0. The book says that the result is the same when AB = 0.

Given the function f (x) = 1 / 2 of a - (x power of 2 + 1), if f (x) is an odd function, what is a =

Using the definition of odd function, we can get
f(x)=a-1/(2^x+1),f(-x)=a-1/(2^-x+1)=a-2^x/(2^x+1)
Because f (x) + F (- x) = 0
So we can substitute 2a-1 for 0
a=1/2
I hope it will help you

He went to the airport to meet his friend

He went to the airport to pick up a friend

(2m + n) (M + n) simplification
Urgent, quick

2m square + 3MN + n square

Given K ∈ R, find the minimum chord length of the line y = K (x-1) + 2 cut by the circle x2 + y2-2x-2y = 0

The equation of the line y = K (x-1) + 2 passing through the fixed point m (1,2), (4 points) circle can be reduced to (x-1) 2 + (Y-1) 2 = 2, then its center is C (1,1), radius is r = 2, (8 points) let the line y = K (x-1) + 2 and the circle (x-1) 2 + (Y-1) 2 = 2 intersect at points a and B, then when cm ⊥ AB, the chord length | ab | gets the minimum value, (12 points) then | cm | = (1-1) 2 + (1-2) 2 = 1, then | am|= R2-12 = 1, so | ab | = 2 | am | = 2

A car travels 167 km in 2 hours and a big car 250 km in 3 hours. What are the speeds of the car and the big car? We should use the knowledge of fraction to solve it!