Suppose a,b,c∈C, and |a|=|b|=|c|=1 and abc=a+b+c, then bc+ca+ab is equal to
Let a, b, c be complex such that ab+bc+ca=12,(a+b+c)=2,abc=4 then the value of 1ab+c−1+1bc+a−1+1ac+b−1 is