Idon't understand the volume and explanation

What is the vertical asymptotes of the function f(x)=x-2/x*2-3x-4

What is the solution set of the quadratic inequality x^2-5< or equal to 0

Use the method of cylindrical shells to find the volume v generated by rotating the region bounded by the curves about the given axis.y = 7ex, y = 7e^-x, x = 1; about the y-axis