# Function in Lambda Calculus

Yesterday I have been trying to complete this exercise. I have to find: $$((map)l)t \simeq \lambda k \lambda x ((k)(t)t_1)....((k)(t)t_n)x$$

where $$l=\lambda k \lambda x ((k)t_1)....((k)t_n)x$$ And $t$ is a generic Lambda term. I tried but without success. Maybe it will be something like that : $$map=(\lambda a \lambda b (\lambda s \lambda d((b(st))d)))$$ Thank you in advance to all will answer