I have a problem where i dont understand how the solutions manual is doing the steps.
Problem: Find the area of the zone of a sphere formed by revolving the graph of
about the y axis.
then, sorry the square root suppose to go over the whole equation.
usually at this point it is
The solutions manual shows
Why did they do this?
Abd the next step is confusing..
Where did the 3 come from?
And in the next step where did the x come from?