The curve x = y2 + 1, showing the portion "under" the curve from y = 1 to y = 5.
In this case, we express x as a function of y:
So the area is given by:
`=45 1/3\ text[sq units]`
Note: For this particular example, we could have also summed it horizontally (integrating `y` and using `dx`), but we would need to break it up into sections first.
Easy to understand math videos: