Use cylindrical shells to find the volume of the solid that is generate when the region that enclosed by , , is revolved about the line

As it said "cylindrical shells" to find the volume.

I transform to

The area of this surface is , and then integrate from a to b to get cylindrical shells formula. For this problem, I changed a to b to c to d. And to

My problem is to be revolved about the line y=1, that means it similar to revolve about x-axis, but higher 1 unit. I don't know how to calculate it.

I don't know how to find y and f(y).

Please help, thank you.