The Ladder at the Wall problem is a good introduction to this one so you are advised to solve it first!
Winnie-the-Pooh of the mass M is climbing the ladder of the length L, which is leaning against the tree trunk (making angle alpha with it).
Friction coefficients are k1 at the bottom end of the ladder and k2 at the top end (as they are touching different types of surfaces).
There is a bee-hive with honey on the tree - which is the goal for the bear - but here is also Piglet - notable Bees Rights Activist.
He is pulling the lower end of the ladder horizontally with the force F.
We want to know, how far Winnie can climb along the ladder before it start sliding (to the right, partly thanks to efforts of Piglet) - so please create formula expressing the maximal height reached.
source: Minarsky