1. Solve the following tasks:
At 1.15 rectilinear segment AB, which connects the two light sources A (power p) and B (force q), find the point M illuminated by the weakest if | AB | = a. (Illumination is inversely proportional to the square of the distance from the light source.)

2. Carry out a full investigation of these functions and build their schedules.
2.15 y = -ln ((1 + x) / (1 - x))

3. Carry out a full investigation of these functions and build their schedules.
3.15 y = ((x - 2) / (x + 1)) 2

4. Find the minimum and maximum values of the function y = f (x) on the interval [a; b]
4.15 y = (1 + lnx) / x, [1 / e; e]