What is the common different of this arithmetic sequence ?

There is a line with slope 1/a going through the point (a, a²). find the equation of the line perpendicular to this line at this point. (don’t let this problem intimidate you! solve the problem as you would if i’d given you specific values. just use variables instead.)

Use composition to determine if (x) or h(x) is the inverse of f(x) for the limited domain x2-1.

Ihonestly have no clue if it's each or none.