use math.na: inv

function zeroes_bisection(f,a,b,n)
   zeroes = []
   h = (b-a)/n
   for k in 0..n-1
      x0 = a+h*k
      x1 = a+h*(k+1)
      if sgn(f(x0))!=sgn(f(x1))
         # print([x0,x1,f(x0),f(x1)])
         if f(x0)==0
            zeroes.push(x0)
         elif f(x1)==0
            zeroes.push(x1)
         else
            zeroes.push(inv(f,0,x0,x1))
         end
      end
   end
   return zeroes
end