A math problem in the third year of junior high school, thank you for solving it, and you will add p

These are all common function problems, and it is recommended that you read more example problems! To wrap it up! That's how you can really master.

Passing points b and c respectively as parallel lines on the x-axis, and intersecting parabolas c1 and c2 at points a and d"Is that right? If there is an intersection, it should be two of each. This question should be able to be made.

Question 1: 1) For the case of n>1, when n is odd, anbn 2) For the case of n>1, when n is odd, an=1 2 an-1, when n is even, an=1 2(1+an-1) Question 2, first give the graph Question 2 x 2+y 2=1, y 2+z 2=2, z 2+x 2=2 y 2=x 2=2-z 2, x 2=y 2=1 2z 2 = 3 2 brings the solved into xy + yz + zx in turn, and the minimum value is 1 2 - root number 3

There is no diagram in the second problem, but it can be done symmetrically, using the principle of the shortest line segment between two points, which can be solved.

Solution: According to the problem, A, B, and C form a triangle, and the angle ACB = 180-30-45 = 105 degrees, the angle ABC = 45-30 = 15 degrees, the angle BAC = 45 + 15 = 60 degrees, the side AB of the triangle ABC is 273 kilometers long, and according to the title, it can be known that the height on the side AB of the triangle ABC should be greater than 85 kilometers.

Therefore, the length of AC should be greater than 85 sin60 degrees = km), the length of BC should be greater than 85 sin15 degrees = km), BC>AB, and the angle bac "angle ACB, contradicts the big side of the triangle against the big angle, and the big angle against the big side.

Therefore, if the height on the side AB of the triangle ABC should be greater than 85 km, and the length of the side AB should be 273 km, then a triangle cannot be formed.

Therefore, if a direct highway between A and B is built, this highway will definitely pass through this natural forest.

The title is wrong, look at the picture I drew for you, according to this question c The city does not exist at all, it is just floating clouds.

c = 90 ° tana = 3 2, so as long as it is satisfied, bc ac=3 2, it is fine.

So you can draw an infinite number of RT triangles.

And these triangles are similar.

The two angles are equal, so the triangles are similar.

Not unique, the two triangles are similar.

Not unique, because it only says tana=3 2, that is, as long as the proportions are right, so there are countless triangles like this, first draw a right angle with a triangle, so that the length of bc is 3, and the length of ac is 2, and it is fine. Just bc ac=3 2.

The opposite of the fourth power of minus two minus two and two-thirds two + five and one-half minus one-sixth minus minus zero two-five.

11 and 5/6

Minus two to the fourth power minus two and two-thirds two + five and one-half minus one-sixth minus minus minus zero two-five.

12 and 1/6