For `a`, `b`,`c in R-{0}`, let `(a+b)/(1-ab)`, `b`, `(b+c)/(1-bc)` are in `A.P.` If `alpha`, `beta` are the roots of the quadratic equation
`2acx^(2)+2abcx+(a+c)=0`, then the value of `(1+alpha)(1+beta)` is