You seem to have misunderstood the purpose of this board. Show us what you have tried and where you have problems and we will attempt to assist you and give hints.
I will say this much- problems 4 and 5 do NOT ask you to solve the equation. They only ask you to show that a given function is a solution. If you were given the equation , and asked to show that x= 2 is a solution, you would NOT attempt to solve the equation- just replace x with the number "2" and see if it works.