How do you learn math in the ninth grade?,It s so difficult.。

I agree with the point from upstairs.

Actually, I think it's okay! The foundation is more important to pull...

If you have just entered the ninth grade, you must pay attention to graph geometry and functions! Buy more books for yourself, don't give up asking the teacher as soon as you have a problem, think about it yourself, and ask the teacher again if you can't solve a problem within an hour!

At the beginning, if you feel that you have difficulties, you can not overcome the problem first, it is the last big question of a paper, first get the score in front of a paper, especially the multiple-choice questions, absolutely no points can be deducted!

The experience of the past tells you that the mathematics of the high school entrance examination is very simple, do not have any pressure, do not listen to the teacher to say that the high school entrance examination is so terrifying, as long as the usual grades are stable, there will be no major problems in the high school entrance examination, unless you are too nervous. Just like this year's high school entrance examination, my classmates and I walked out of the exam room with laughter after finishing the math exam, which is very simple!

I recommend you to find an experienced tutor, it is difficult to learn on your own, and some experienced tutors will summarize the knowledge points themselves, which will be very helpful to you!

I suggest that you still consolidate what you have learned before, because you learn things step by step, step by step, do you think this is difficult, the main reason is that the foundation is not laid, don't be afraid of it, to overcome it, you can ask teachers and parents more, don't be afraid of ugliness, and do more questions, do more questions, form a conditioned reflex, really, that's how I came.

Quadratic equations and quadratic functions are the main points.

Use the Pythagorean theorem to find out that the third side is equal to 2 2x

It can be seen that tan b is 2 2

It's not hard. 1. Corresponding to the figure with equal angles and unequal corresponding edges, similar; Figures with equal corresponding angles and equal corresponding edges, congruent.

In the ninth grade, I mainly learned about triangles, and of course, I should also know that all equilateral triangles are similar, and all squares are similar,..i.e. all regular n-sided shapes are similar.

1) Isosceles triangle: isosceles triangles with equal apex angles are similar; Isosceles triangles with equal base angles are similar; Equilateral triangles are similar.

2) Right triangle: In addition to right angles, there is an angle that corresponds to an equal right triangle; Isosceles right triangles are similar.

3) Arbitrary triangle: There are two angles corresponding to the similarity of equal triangles.

4) The inner angles of similar triangles correspond to equals.

5) Congruent triangles are special similar triangles, and their corresponding angles are equal and their corresponding sides are equal.

2. A triangle with two sides corresponding to a proportional triangle is a similar triangle, such as a a'=b/b'

Learn the basic concepts well, do more questions, and summarize more.

Listen to it in class, do it after class, and do it repeatedly.

Listen carefully in class and do more questions. The concepts should be memorized, and the types of questions should be known when doing the questions, and they should be flexible. Ask more, think more.

It is not only necessary to lay a good foundation, but also to master the exam skills.

Finding a tutor to tutor can improve quickly. Online tutoring, as long as there is a headset and a camera, can achieve the equivalent of face-to-face teaching in life, turn on the computer to attend classes, so that your problems do not stay overnight. is your best choice.

If you can't learn well, you must not be able to keep up with the teacher's footsteps, so you can only review and review more after class, don't want to become a fat person in one bite, and the key is to deal with the wrong questions. Just a little bit of progress.

Of course, listen carefully in class and practice more after class, but the important thing is to master the learning method that suits you.

Grade 9 is based on Grade 7 and Grade 8 math, so learn grades 7 and 8 well and then look at grade 9 math. Read the example questions in the textbook first, and then do the exercises to consolidate.

Listen to the teacher's lectures, do the questions carefully, accumulate experience in making mistakes, and prepare for the high school entrance examination.

I think the most important thing is to memorize the formula, and when you are familiar with the formula, you can transform and use it yourself, and then it is very simple.

Arrange time reasonably, work steadily, step by step. Supplemented with an appropriate amount of questions.

1. The intersection point of the parabola and the y coordinate axis is a, that is, x=0, and a(0,c); ac is a chord, so p(c 2,0), so the radius of the circle p pa 2=op 2+oa 2=c 2+(c 2) 2; Similarly, the radius pe 2=pf 2+ef 2=(c 2+1) 2+1 2; The two equal radii are solved to give c=2, so b(2,2).

2. Simplicity. From the solution of one middle school, each point sits on the quiet object mark, and the certificate is pm 2 = pe 2 + me 2.

3. The straight line EF is the symmetry axis of the parabola, requiring the shortest circumference, that is, AQ + CQ being the shortest, making the axisymmetric point A' of point A about the straight line EF, connecting A'C, and the intersection point with EF is the Q point when the perimeter is the shortest, which is the use of the mirror principle, the shortest straight line between two points. Then find the relationship between S t: subtract the area of the triangular opening liquid CFQ from the area of the trapezoidal OAQC, and note that the Q point does not coincide with the N point.

PS: Draw more pictures when doing the questions.

As shown in the figure, a naval base is located at A, there is an important target B 200 nautical miles due south, there is an important target C 200 nautical miles due east of B, Island D is located at the midpoint of AC, there is a supply dock on the island, Island F is located on BC, just in the direction of due south of Island D, a ** departs from A, cruises at a constant speed through B to C, and a supply ship departs from D at the same time to west-southward and sails in a straight line at a constant speed, wanting to deliver a batch of items**, it is known that the speed of ** is 2 times that of the supply ship,** If you meet a supply ship at point E on the way from B to C, how many nautical miles did the supply ship sail at the time of the encounter?

e between bf).

Solution: Analyze the problem and know ab=bc=200 (nautical miles).

If the speed of the supply ship is v and the meeting time is t, then the ** speed is 2v

At the time of the encounter, ** traveled ab+be = 2v)t = 2vt

The supply ship travelled de = vt

From the above two formulas, it is easy to know that ab+be = 2de, that is, de=(ab+be) 2

Let be=x, then ef=bf-be = (1 2)bc-be = 100-x

de=(ab+be)/2 = 200+x)/2

df = 1/2)ab =100

In the triangle def, it is known by the Pythagorean theorem EF squared + df squared = de squared.

Bring the data in.

100-x)*(100-x)+100*100=[(200+x)/2]*[200+x)/2]

Solve the equation as: x=(400-200*root number 6) 3 or x=(400+200*root number 6) 3 (discarded if not in place).

The last solvable de = 200+x) 2 = 500-100*root number 6) 3

The secondary value is approximately equal to nautical miles), Answer: Then the supply ship sailed (500-100 * Gen No. 6) 3 (or nautical miles) at the time of the encounter.