(a+b+c)^2 equal to _____.
A. a2+ b2+ c2 – 2(ab+ bc+ ca)
B. a2+ b2+ c2+ 2(ab – bc – ca)
C. a2 – b2 – c2 – 2(ab+ bc+ ca)
D. a2+ b2+ c2+ 2(ab+ bc+ ca)
Correct Answer: D. a2+ b2+ c2+ 2(ab+ bc+ ca)
A. a2+ b2+ c2 – 2(ab+ bc+ ca)
B. a2+ b2+ c2+ 2(ab – bc – ca)
C. a2 – b2 – c2 – 2(ab+ bc+ ca)
D. a2+ b2+ c2+ 2(ab+ bc+ ca)
Correct Answer: D. a2+ b2+ c2+ 2(ab+ bc+ ca)