Question

We know that
abc=-3
ab+bc+ac=-4
a+b+c=1

Find (a+b)(a+c)(b+c)

Answer 1

(ab+bc+ac)(a+b+c) = a^2b + a^2c + ab^2 + ac^2 + b^2c + bc^2 + 3abc
(a+b)(a+c)(b+c) = a^2b + a^2c + ab^2 + ac^2 + b^2c + bc^2 + 2abc
subtract and you get
(ab+bc+ac)(a+b+c) - (a+b)(a+c)(b+c) = abc
I guess you can finish up now, eh?

Answer 2

Thank you sir