Help with an 'Area Under a Curve' question please?
Estimate the area of the given function, f(x) = x^2 + 1 using 4 inscribed rectangles on the interval [2, 4].

Question

Help with an 'Area Under a Curve' question please?
Estimate the area of the given function, f(x) = x^2 + 1 using 4 inscribed rectangles on the interval [2, 4].

anonymous · Answer

I just about finished this when I realized I made a mistake. 
Now I'm confused. Help is appreciated! I'll post some of my work:

anonymous · Answer

where's your work... i'll have a look

anonymous · Answer

so since there are 4 rectangles, the width would be 0.5, I thought. but inscribed means lower which means they only want the lower sum I think.
so I would = 3 and 4 right?
but from 3 to 4 4 rectangles would have to make I= 0.25 or 1/4?

anonymous · Answer

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