Visual inspection, pinyin mü cè, visualization, and the method of estimating distance, height and angle with eyes; Distance is measured by eyes without instruments, only by naked eyes. In fact, this is a military ranging method, called arm length ruler, which is used to measure distance.
Visual inspection is to judge the distance according to vision, target clarity and practical experience. The commonly used methods are comparison method and judgment method.
Is to compare the distance to be measured with the known distance. You can also divide the distance to be measured into several sections and compare them to calculate the total length.
Question 2: math diary, I learned to write by walking and visual inspection. During May Day, my mother and I went to the mall to buy clothes. But I think the price there is very strange: saying "buy 100 to send 100" means no money?
Mother said, "Silly daughter, how can you not use money?"
I said, "Because it says buy 100, get 100, which means 100- 100=0, so no money is needed!"
Mom said, "that's how you calculate." If so, everything in the mall is free, and many guests will come. This mall will lose a lot. "
Mom also said that you only need 50 yuan to buy 100 and get 100, you know?
After listening to my mother's analysis, I still don't understand. Why? It seems that I still have to go to the shopping mall to make a serious investigation or consult Ceng Laoshi to see what she has, because I know there is still a lot of math knowledge I haven't understood yet.
Question 3: I want to know what this number means! Visually, it is QQ number. You can try again. It's too difficult. You should limit it to a certain range.
Question 4: What does it mean that a girl sends me a bunch of math? 10 before 520 13 14 means I love you all my life, and it may be fun in the future.
Question 5: What exactly does digital HD mean? Digital TV is the third generation TV after black-and-white TV and color TV. Digital TV refers to a TV system or TV equipment that uses digital signals in the process of processing, transmitting, transmitting and receiving TV signals. The specific transmission process is: the image and sound signals sent by TV stations are digitally compressed and modulated to form digital TV signals, which are transmitted by satellite, terrestrial broadcast or cable, and then received by digital TV, and the original images and sounds are restored through digital demodulation and digital video and audio decoding. Because the whole process is processed by digital technology, the signal loss is small and the receiving effect is good. Compared with analog TV, digital TV has the advantages of 1, good viewing effect, high image definition and high sound quality, which meets people's sensory needs. 2. Strong anti-interference ability. Digital TV is not susceptible to boundary interference, which avoids the influence of crosstalk and noise. 3. High transmission efficiency. 8- 10 sets of standard definition digital TV programs can be transmitted by using analog channels in cable TV network. 4. Compatible with existing analog TV sets. You can watch digital TV programs by installing a digital set-top box in front of an ordinary TV. 5. Provide brand-new services.
Question 6: What do the numbers on the color block below mean? Color index
Color is divided into four dimensions: lightness, purity, hue and warmth.
When designing and drawing, a palette pops up, but the palette has color difference visually, so the color is divided into 1- 100 as the index. Entering the corresponding value will produce the corresponding color difference.
The above picture can be called a color chart.
There is a colorimetric tower in the design institute. You'll know when you read it.
Question 7: Take the midpoint E and F of PA and Pb and connect Me, ED, FN and FD respectively.
In right triangle APM, ME=AP/2=AE. Angle MEP= Angle EAM+ Angle AME=2* Angle EAM.
In the triangle ABP, FD=AP/2 (the center line is half of the base).
So, ME=FD
Similarly, ED=NF, angle NFP=2, angle NBP, angle MEP= angle NFP.
It is easy to draw that the quadrilateral PEDF is a parallelogram, so the angle PED= the angle PFD. (Diagonal lines are equal).
Then, angle MED= angle NFD,
So triangle MED is congruent with triangle DFN (SAS)
So it is proved that DM=DN.
Question 8: Mathematics seeks to find out the laws of these numbers! ! The biggest number in the sixth box is 63, so what's the biggest number in the seventh box? Isn't there a seventh reward box? If there is, it's against the rules. You see, starting with the first number in the first box, the first number in every other box must be multiplied by 2. If there is a seventh box, the first number should be 64, and the last one, the largest one, is 95.