The logarithmic function of 1, the radix is greater than 0, and the real number greater than 0 is not 1.
Scheme b is correct.
The 2y power of 2 7 is first changed to the y power of 49.
Then according to the first equation, x=log2 A (footprints are not easy to type, and there are many questions, so make do with it.
. . . )
y=log49 A
Bring it in, and combine the same basis points by using the basis-changing formula. The sum is equal to one, that is, the numerator and denominator are the same. A.
The case is 98
3 change the y=x square into the x=y square, and just turn the image 90 degrees.
4. The accuracy of dichotomy is direct;
Given the precision ξ, the steps of finding the approximate value of the zero point of the function f(x) by dichotomy are as follows:
1 determine the interval [a, b] and verify f (a) f (b)
Find the midpoint c of the interval (a, b).
3 calculate f (c).
(1) If f(c)=0, then c is the zero point of the function;
(2) If f (a) f (c)
(3) If f (c) f (b)
(4) judging whether the accuracy ξ is reached: that is, if | a-b |
Answer 2-4.
Since it is 0. 1, then divide by 2 every time, the first time is 0.5 and then 0.25, and the fourth time is 0. 125.
Do it.
In space 5, four points that are not on the same plane directly connect a tetrahedron. . .
6 Putting the condition "the distance to the straight line is 1" into the image is equivalent to translating the straight line up and down several times.
Bit, two straight lines and a circle intersect, and the most valuable part is the sum of straight lines that move up and down.
The circle is tangent, the thinking is clear, and the specific calculation is not difficult. The answer is that the range of C is (-13, 13).
To put it more simply, if the distance from four points to a straight line is 1, then the distance to a straight line is 1.
Two straight lines and a circle each have two intersections (using the idea of symmetry axis, this is the only case), then the straight line
In the case of maximum, the original straight line is tangent to X +Y = 1, so it should be clear to draw it.
The second photo;
Diagonal mapping; I guess you forgot how to draw an oblique survey. Du Niang said:
(1) Establish a plane rectangular coordinate system: take the X axis and Y axis perpendicular to each other in the known plane figure, and the two axes are in phase.
At o'clock.
(2) Drawing oblique coordinate system: Draw the corresponding X' axis and Y' axis on the paper (plane) drawing vertical drawing.
The two axes intersect at o'
∠x'O'y' =45 degrees (or 135 degrees), and the plane they determined represents the horizontal plane.
(3) Draw the corresponding figure: Draw the line segment of the known figure parallel to the X axis in the vertical view.
, the length remains unchanged.
It is known that the line segment parallel to the Y axis in the figure is drawn parallel to the Y' axis in the orthographic drawing, and the length is the original.
Half.
(4) For general line segments, draw a vertical line from each endpoint of the line segment in the original drawing, and then follow the above requirements.
Draw these line segments, determine the endpoints, and draw line segments.
The height line length of the original image is 2. . .
The third one;
Two times two vertical, there is only one way to say, that is, the corner. Did you see what was inside? Plane a is perpendicular to plane b,
Just because the A plane is perpendicular to the C plane does not mean that the B plane is perpendicular to the C plane. It is strongly recommended to cut some pieces of paper and then swing it.
The fourth;
I knew it the first time I saw such a picture. Compared with the four-point circle thought of plane geometry in junior high school,
After connecting DE in the graph, the length of DE is equal to AE. To put it bluntly, the median line on the hypotenuse of a right triangle is equal to half of the hypotenuse, and the rest is simple. AE is perpendicular to DCB, so AE is perpendicular to DE, and Pythagorean theorem holds. . .
Pure hands, I hope I can help you. Come on.