Question

Find ab + ab + ac + 2 ab

Answer 1

The answer assuming that  a,b,c are real is

[{(a+b+c)^2 - a^2 - b^2 - c^2}/{2*(cos2Ф+2(sinФ)^2)}] -bc + 3ab

assuming a=b=c=1, we have ans. (2Ф - 1)^2 where Ф denotes the golden ratio

Answer 2

Answer:

Step-by-step explanation:

The answer assuming that  a,b,c are real is

[{(a+b+c)^2 - a^2 - b^2 - c^2}/{2*(cos2Ф+2(sinФ)^2)}] -bc + 3ab

assuming a=b=c=1, we have ans. (2Ф - 1)^2 where Ф denotes the golden ratio