F (SiNx) = cos2x, f (x) range is

F (SiNx) = cos2x, f (x) range is

f(sinx)=cos2x=1-2sin²x,
Then f (x) = 1-2x & # 178; (- 1 ≤ x ≤ 1),
Then f (x) is [- 1,1]

A simple algorithm for (- 666)

-(1998+1)(1998-1)/1998*1998*1/3

1. The thickness of the flat mirror is 2cm. When you stick your finger on the mirror, the distance between your finger and the image is ()
A.2CM B.4CM C.1CM D.6CM
2. XX brand table lamp has a lampshade. Its inner surface is very smooth. Its function is to concentrate the light on the place where it needs to be illuminated as much as possible. It uses ()
A. The reflection angle of light is equal to the incidence angle B. light travels along a straight line in the same substance
Don't choose any amount
The second option B is wrong. It is the reflection of light and the light path is irreversible

1.B
2.A

What is the area formula of trapezoid with letters? What is the area formula when parallelogram is 0? What is the shape of trapezoid
What is the area formula of trapezoid indicated by letters? What is the area formula of parallelogram? When the top and bottom of trapezoid is 0, what is the shape of trapezoid and what is the area formula?

The rectangle is derived from the number lattice, the square is derived from the area formula of the rectangle, the parallelogram is divided into two parts along the height, and then put together into a rectangle, the length of the rectangle is the bottom of the parallelogram, the width of the rectangle is the height of the parallelogram, and the area of the rectangle is the area of the parallelogram

Simple calculation of 62 * 38 + 38 * 38

The original formula is equal to (62 + 38) * 38
=3800

Conditions:
Salary: 50% shopping: 25% insurance: 5% tax: 8% Management: 12%
Answer the questions according to the conditions. The insurance expense is 10000 yuan. What are the other items?

Salary: 100000 yuan
Shopping: 50000
Tax: 16000
Management: 24000

As shown in the figure, in ▱ ABCD, be ⊥ ad at point E, BF ⊥ CD at point F, AC and be, BF intersect at points g and h respectively. (1) prove: △ BAE ∽ BCF; (2) if BG = BH, prove: quadrilateral ABCD is diamond

It is proved that: (1) be ⊥ ad, BF ⊥ CD, ABCD is parallelogram, Bae is BCF, 3 is BCF, 2 is Bae is BCF, 4 is BG is BH

Is the order of magnitude not the power of 10 in the scientific counting method? Why is it said that the order of magnitude of molecular diameter is 10 ^ - 10m in physics?
According to the definition of order of magnitude, shouldn't the order of magnitude of molecular diameter be - 10? Why does the order of magnitude have units?

-10 is the order of magnitude, but the order of magnitude is used to explain the difference between things, there are units to compare
The order of magnitude of molecules in meters is - 10
If it's centimeter, it's - 8

What is the volume of the largest cylinder made of a cube wood with an edge length of 12 decimeters?

3.14 × (122) 2 × 12, = 3.14 × 36 × 12, = 1356.48 (cubic decimeter). A: the volume of this cylinder is 1356.48 cubic decimeter

The perimeter of a rectangular grassland is 270 meters, and the ratio of length to width is 5:4. The area of this grassland is 1______ Square meters

The length of the rectangle is (270 △ 2) × 55 + 4 = 75 (m) the width of the rectangle is (270 △ 2) × 45 + 4 = 60 (m) the area of the rectangle is: 75 × 60 = 4500 (M2) a: the area of this land is 4500 square meters. So the answer is 4500