If A-B = B-C = 3 / 5 and a & # 178; + A & # 178; + A & # 178; = 1, find the value of AC + BC + AC

a-b=3/5①
b-c=3/5②
By adding the two formulas, we can get a-c = 6 / 5
Then add the a-c = 6 / 5 square to get the following result:
2(a^2+b^2+c^2)-2(ab+bc+ca)=54/25
Because a ^ 2 + B ^ 2 + C ^ 2 = 1, AB + BC + AC = - 2 / 25

RELATED INFORMATIONS

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