If (a-4)2 + (b-7)2 + (c - 11)2 = 0
find the value of a² + b² + c² - abc.
Answer & explanation
Correct answer: option 1
If (a-m)2 + (b-n)2 + (c - o)2 = 0
then a - m = 0
b - n = 0
c - o = 0
So, a = 4
b = 7
c = 11
Now, a² + b² + c² - abc = 4² + 7² + 11² - 4x7x11 = 16 + 49 + 121 - 308 = -122