Let a and B belong to R. if the function LG (1 + ax) / (1 + 2x) defined in the interval (- B, b) is an odd function, the range of a + B is obtained

Let a and B belong to R. if the function LG (1 + ax) / (1 + 2x) defined in the interval (- B, b) is an odd function, the range of a + B is obtained

Let C be any number in the interval (0, b), then LG (1 + AC) / (1 + 2C) = - LG (1-ac) / (1-2c), that is
(1 + AC) / (1 + 2C) = (1-2c) / (1-ac), 1-A ^ 2C ^ 2 = 1-4C ^ 2, so a ^ 2 = 4
Since (- B, b) is a symmetric interval, the definition of function (1 + ax) (1 + 2x) is greater than 0

A cone-shaped grain pile is 1.2 meters high and covers an area of 16 square meters. Put this pile of grain into the granary, which accounts for 27% of the whole granary. Calculate the volume of the granary

13 × 16 × 1.2 △ 27, = 6.4 △ 27, = 22.4 cubic meters; a: the volume of this granary is 22.4 cubic meters

Given that the ellipse is x ^ 2 / 4 + y ^ 2 = 1, find the trajectory equation of the midpoint of the parallel chord cut by the straight line with slope 1

AB midpoint P (x, y) K (AB) = (Ya Yb) / (XA XB) = 1xa + XB = 2x, Ya + Yb = 2Y [(XA) ^ 2 / 4 + (ya) ^ 2] - [(XB) ^ 2 / 4 + (Yb) ^ 2] = 1-1 = 0 (XA + XB) * (XA XB) / 4 + (Ya + Yb) * (Ya Yb) = 02x / 4 + 2Y * (Ya Yb) / (XA XB) = 00.25x + y * 1 = 0x + 4Y = 0

A triangle and a parallelogram have the same area and the same base. The height of the triangle is 16 cm. How many cm is the height of the parallelogram

∵ the area of a triangle = bottom × height △ 2, the area of a parallelogram = bottom × height, the area and bottom of a triangle and a parallelogram are equal,
The height of the triangle △ 2 = the height of the parallelogram,
The height of a triangle is 16 cm,
The height of parallelogram is 16 △ 2 = 8 (CM)

The product of two continuous non-zero natural numbers must be () a, odd B, even C, prime D and composite

B even
Because it's a continuous natural number, so
Suppose the first is odd and the second must be even
Suppose the first is even and the second is odd,
Odd number x even number = an even number
So it must be even

If the side length of an isosceles triangle is 4cm and the other side is 9cm, then the perimeter of the isosceles triangle is____

22CM

As shown in the figure, PA is tangent to ⊙ o at point a, and the extension line of Po intersects with ⊙ o at point C. if the radius of ⊙ o is 3, PA = 4. The length of chord AC is ()
A. 5B. 455C. 655D. 1255

Connect Ao, AB, because PA is tangent, so ∠ Pao = 90 °, in RT △ Pao, PA = 4, OA = 3, so Po = 5, so Pb = 2; ∵ BC is diameter, ∵ BAC = 90 °, because ∠ PAB and ∠ Cao are the residual angle of ∠ Bao, so ∠ PAB = ∠ Cao, and ∠ Cao = ∠ ACO, so ∠ PAB = ∠ ACO, and

As shown in the figure, from a to B, you need to pass through a small river (the river banks are parallel). Now, if you want to build a bridge Mn on the river (Mn is perpendicular to the river bank), how can you choose the location of the bridge to make the shortest distance from a to B?
XiaoCong's method is: cross point a as the vertical line of the river bank, take AC equal to the river width, connect BC, cross the river bank on one side at point n (closer to point B). Cross point n as Mn, perpendicular to the river bank on the other side at point m, then Mn is the required value
Try what you have learned to judge whether the method is correct. If not, write your method. If you think it is correct, write the reason

Let a be a, B be B, connect AB, make AB vertical bisector, CD intersect C and D, AB CD intersect o, respectively
The distance between the two banks (vertical line) crossing point O, the two banks connecting point E and point F, AE EF FD is the shortest distance

OC and od are two rays in ∠ AOB, OE bisects ∠ AOC, of bisects ∠ BOD
One question: if ∠ AOB = 120 °, COD = 20 °, calculate the degree of ∠ EOF
Problem 2: if ∠ EOF = α, ∠ cod = B, find ∠ AOB. (expressed by algebraic formula containing α and b)

1.∠EOF=∠EOC+∠COD+∠DOF=0.5∠AOC+∠COD+0.5∠DOB=0.5(∠AOC+∠DOB)+∠COD=0.5(∠AOB-∠COD)+∠COD=0.5*(120°-20°）+20°=70°2.∠EOF=∠EOC+∠COD+∠DOF=0.5∠AOC+∠COD+0.5∠DOB=0.5(∠AOC+∠DOB)+∠COD=0.5(...

Given the complete set u = {1,2,3,4,5}, a = {x 2-5x + q = 0} and a ≠ &;, a is contained in U, find CUA and Q

A is not an empty set
So △ > = 0 → 25-4q > = 0 → Q