The function y = f (x) defined on R satisfies f (- x) = - f (x), f (1 + x) = f (1-x) when x ∈ (0,1] f (x) = root sign (x + 1), then the value of F (2011) is

The function y = f (x) defined on R satisfies f (- x) = - f (x), f (1 + x) = f (1-x) when x ∈ (0,1] f (x) = root sign (x + 1), then the value of F (2011) is

F (1 + x) = f (1-x) deduces f (1 + x-1) = f (1-x + 1) to get f (x) = f (2-x) and f (- x) = - f (x), so f (2-x) = - f (- x), that is, f (2 + x) = - f (x) deduces f (4 + x) = - f (x + 2) to get f (x + 4) = f (x), so the function period is t = 4, so f (2011) = f (5.3 * 4-1) = f (-)

25 calculation questions of binary linear equations

1.2x+9y=813x+y=342.9x+4y=358x+3y=303.7x+2y=527x+4y=624.4x+6y=549x+2y=875.2x+y=72x+5y=196.x+2y=213x+5y=567.5x+7y=525x+2y=228.5x+5y=657x+7y=2039.8x+4y=56x+4y=2110.5x+7y=415x+8y=4411.7x+5y=543x+4y=3812.x...

An applied problem about binary linear equations
There are three rooms, double rooms and single rooms in the room department of Red Sun Hotel. The charge is 50 yuan per person per day for three rooms, 70 yuan per person per day for double rooms and 100 yuan per person per day for single rooms. In order to attract passers-by, preferential treatment is offered during the May Day golden week, and 50% discount is given for all group stay. A 50 person tour group will stay in the hotel on May 2, I rented some ordinary rooms with three or double rooms, and each room was just full. It cost 1510 yuan a day
Q: how many rooms do you rent for three or double rooms?

"Ice rain and butterfly flying"
Golden Week discount: 25 yuan per person for three rooms, 35 yuan per person for double rooms
Let three rooms rent x rooms and double rooms rent y rooms
(1) Formula: 3x + 2Y = 50
(2) Formula: 25 (3x) + 35 (2Y) = 1510, simplification: 75X + 70Y = 1510
From formula (1) multiplied by 25, formula (3): 75X + 50y = 1250
From (2) - (3), 20Y = 260
y＝13
By substituting y into (1), we get 3x + 26 = 50
3x＝24
x＝8
A: eight for three and 13 for two
Checking calculation: 3 × 8 + 2 × 13 = 50 (checking calculation is correct)
Good luck and goodbye

It is known that a = (2,1) B = (1, - 3) and C = (3,5). Take a and B as a group of bases, and use a and B to indicate that C vectors are all vectors

Let C = XA + Yb, (where x and y are real numbers)
That is, (3,5) = x (2,1) + y (1, - 3)
Then 3 = 2x + y, 5 = x-3y
The solution is x = 2, y = - 1
∴c=2a-b.

In the isosceles triangle ABC, the angle ABC is 120 degrees, the point P is a moving point on the bottom edge AC, and m and N are the midpoint of AB and BC, respectively. If the minimum value of PM + PN is 2,
What is the perimeter of the triangle ABC

Mn is the median of △ ABC. When PM + PN is the smallest, it is an equilateral triangle
｜ Mn = half AC
∴MN＝PM＝PN＝1
∴AC=2
High be ⊥ AC through point B
ABC is an isosceles triangle
Three lines in one
The AC of AE = half is 0.5
∵ ABC is an isosceles triangle ∠ B = 120 degrees
∴∠A=∠C=30°
Be = half ab
Let be be be X
0.5 square + x square = (2x) square
So AB came out
Because AB = BC
So you know the perimeter

If x + 2Y = 3, then the square of 6x + 24xy + 24y-8=

6x²+24xy+24y²-8
=6(x²+4xy+4y²)-8
=6(x+2y)²-8
x+2y=3
simple form
=6×3²-8
=6×9-8
=54-8
=46

The distance between P (2,11 / 6 π) and PSIN (Θ - π / 6) = 1 in polar coordinates is

The formula on the right is expanded to the root 3 / 2 Y-1 / 2 x = 1, and the formula on the left is (root 3, - 1). I think it will?

The two right angles of a right triangle are 6 cm and 8 cm respectively. If the right angle side with the length of 6 cm is taken as the axis to rotate for one circle, the volume of the cone is much larger
Less cubic centimeter

After one revolution, the bottom radius of the cone is 8 cm, and the height is 6 cm
The volume of the cone
=3.14*8*8*6/3
=401.92 cm3

How many meters is 0.1km

0.1km is equal to 100m

Given that x is greater than 1 and X ≠ 4 / 3, f (x) = 1 + logx3, G (x) = 2logx2, try to compare the size of F (x) and G (x)
Given that x ＞ 1 and X ≠ 4 / 3, f (x) = 1 + logx3, G (x) = 2logx2, try to compare the size of F (x) and G (x)
Logx3, X is the base number, 3 is the true number, and the following is the same,

f(x)=1+logx3=logx(3x),g（x）=2logx2 =logx4
When 1