Given that a, B and C are three sides of △ ABC, and A2 + B2 + C2 = AB + AC + BC, then △ ABC is () A. Isosceles triangle B. right triangle C. equilateral triangle D. isosceles right triangle

Given that a, B and C are three sides of △ ABC, and A2 + B2 + C2 = AB + AC + BC, then △ ABC is () A. Isosceles triangle B. right triangle C. equilateral triangle D. isosceles right triangle

The original formula can be reduced to 2A2 + 2B2 + 2c2 = 2Ab + 2Ac + 2BC, that is, A2 + B2 + C2 + A2 + B2 + c2-2ab-2ac-2bc = 0; according to the complete square formula, we can get: (a-b) 2 + (C-A) 2 + (B-C) 2 = 0; from the properties of non negative numbers, we can know that A-B = 0, C-A = 0, B-C = 0; that is, a = b = C. so △ ABC is an equilateral triangle, so we choose C

English translation
1. Commodity display
2. Product description
3. Description of postage
4. Contact information
5. Commodity classification
I heard that Better
7. Credit evaluation
8. High quality
9. Fashion
10. Beautiful
11. Generous
twelve

Goods showgoods descriptionpost explain contact quomodogoods sort * * sounds better credit approve high quality commodity generic

The number of solutions to the equation a ^ x + x ^ 2 = 2 (a > 0, a is not equal to 1) should be explained in detail

The original equation can be regarded as the number of intersections of function Y1 = a ^ X and function y2 = (x ^ 2) + 2
The following is a classified discussion:
00, a is not equal to 1)

For high school phrases ending in out, such as take out
If you want to write down all the meanings, there will be more than one
Write the whole idea

Look out

1251017.4361118.9871219. Analyze the rule of arrangement

1 2 5 10 17
4 3 6 11 18
9 8 7 12 19
16 15 14 13
Is that so?

A four character word in the form of (noun) (adjective) (noun) (adjective)
300,

Beautiful scenery, high mountains and long rivers, dark night and high wind, red and wine, bright flowers and dark willows, beautiful weather, high sky and light clouds, perfect combination of pearls and pearls, deep water and fiery heat, round fat and thin, pearly jewel, sharp tongue, pure and clean

How to reduce root 8 to double root 2?

√8=√﹙4×2﹚＝√4×√2=2√2

The usage of look in an English phrase problem
------at from where I stand,the chicks looked like little round yellow balls.
A.Looking B.Look C.To look D.Looked
What else are there such phrases as = = above? The secret of this kind of problem is so easy to confuse

Select D
The logical subject of look is the chicks, which is a passive relation. In this kind of questions, you mainly distinguish who is the executor of the action and who is the executee, so as to determine whether the verb uses the present participle or the past participle
Sincerely serve you!

In △ ABC, CD ⊥ AB, f is the midpoint of BC, FG ⊥ DC, DG = GC

Ab ⊥ CD, GF ⊥ CD, we get that GF is parallel to AB, f is the midpoint of BC, FG is the median line, G is the midpoint of DC, DG = GC

There is an apple on the desk.
Ask a question about this sentence
___ ___ ___ ___ ___ on the desk?
Explain why!

Do you know what is on the desk