If we know the square of a + the square of B + the square of C - AB BC AC = 0, we can judge the size relation of ABC quickly
Square of 2A + square of 2B + square of 2C - 2ab-2bc-2ac = 0
Square of (a-b) + square of (A-C) + square of (B-C) = 0
a=b=c
RELATED INFORMATIONS
- 1. In △ ABC, ∠ ABC = 90 degrees, D, E on AB, ad = AC, be = BC, try to judge whether the size of ∠ DCE is related to the size of ∠ B, if so, ask for the relationship between them, determine the degree, and explain the reason wait anxiously A |\E | D C -----------B Can't upload graphics, so that means. I hope I can understand it. A. B and C are △ and there are lines from e to C and D to C respectively.
- 2. Given a & # 178; + B & # 178; + C & # 178; = AB + AC + BC, judge the relationship between a, B and C
- 3. Given that the lengths of three sides of a triangle a, B, C satisfy a & # 178; + B & # 178; + C & # 178; - AB BC AC = 0, try to judge the shape of the triangle
- 4. If the square of a + the square of B + the square of C - AB BC AC = 0, try to explore the size relationship between ABC
- 5. It is known that a, B and C are the three sides of the triangle ABC. The comparison of the square of (a + B + C) is 2 (AB + BC + AC)
- 6. The square of ab-b-bc + AC Factorization
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- 11. Prove that a ^ 2 + B ^ 2 + C ^ 2-ab-ac-bc is a nonnegative number
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- 15. Given △ ABC, linear L ⊥ AB, l ⊥ AC, prove L ⊥ BC
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- 19. There is a mathematical problem: a natural number a, a total of 10 divisors, including 1 and a, to find the product of these divisors
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