As shown in the figure, use square area to explain the formula: (a + B + C) 2 = A2 + B2 + C2 + 2Ab + 2Ac + 2BC

As shown in the figure: (a + B + C) 2 = S1 + S2 + S3 + +S9=a2+b2+c2+2ab+2ac+2bc．

RELATED INFORMATIONS

1. Let a, B, C ∈ [0,2], and prove that 4A + B ^ 2 + C ^ 2 + ABC ≥ 2Ab + 2BC + 2ca
2. Observe two formulas: the square of a + B + C and the square of a + B + C + 2Ab + 2BC + 2ca,
3. Factorization of 2 (a ^ 2-3ac) + a (4b-3c)
4. It is known that (a + b) divided by 2Ab = 3, then (3a-7ab + 3b) divided by (a + 3AB + b) is equal to? RT
5. Given that a is not equal to B, and satisfies a ^ 2-3a + 1 = 0, B ^ 2-3b + 1 = 0, find the value of 1 / A ^ 2 + 1 + 1 / b ^ 2 + 1
6. Given that a is not equal to B, and a ^ 2 + 3a-7 = 0, B ^ 2 + 3b-7 = 0, find the value of (1 / a) + (1 / b)
7. It is known that: (a + b) &# 178; = 11, (a-b) &# 178; = 5, then the value of a & # 178; + B & # 178; is equal to_____
8. If ABC is three positive numbers, and satisfies a + B + C = 18,1  a + B + 1  B + C + 1  C + a = 10  9, then what is the value of a  B + C + B  C + A + C  a + B?
9. Given that | a + & # 189; | + | B + 3 / 10 | + | C-9 7 / 10 | = 0, then ABC =?
10. It is known that ABC is an integer that is not zero, 7 / 2 equals 9 / 5 equals 10, only 21, ABC is arranged from small to large
11. A-B + C = 5, find the value of a ^ 2 + B ^ 2 + C ^ 2-2ab-2bc + 2ca
12. In △ ABC, if 3a2 + 3b2-3c2 + 2Ab = 0, then Tanc=______ ．
13. Given that a: B: C = 2:3:4 and 3a + 5b-4c = 15, find the values of a, B and C
14. If a + B = - 1, what is the value of the algebraic formula 3A (a + b) - 5a-5b + 7
15. If a + B = - 1, find the value of algebraic formula 3 [a + b] - 5a-5b + 7 Formal addition and subtraction {two}
16. Point out the coefficients of each of the following algebraic formulas: negative 2Ab + 5B 2 / 5A minus 7 / b
17. How to simplify a (3a squared b-ab squared) - (AB squared + 3A squared b)
18. How to simplify 3A's square + 5A's square + b-ab Good answer, additional points! Given that A.B is the root of two real number solutions of equation 3x + 4x-7 = 0, find the value of 3A's square + 5A + b-ab
19. If (the M-1 power of X multiplied by the N + 4 power of Y) multiplied by (the 5m power of X multiplied by Y) = the fifth power of X multiplied by the sixth power of Y, the n power of M is calculated
20. 270 ml is equivalent to a few parts of a liter