function bisect(a,b)
    c=0
    for i=1:10
        c=(a+b)/2
        y=f(c)
        if y<0
            println("updating a with ",c)
            a=c
        else
            println("updating b with ",c)
            b=c
        end
    end
    return a,b
end

f(x)=x^2-2
bisect(0.0,2.0)