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Having trouble with these two problems:

1. If f(x) = ln(x)/x (3 <= x <= 10), find an expression for the area under the graph of f as a limit. Do not evaluate the limit.

My answer:

Change in x = (10 - 3)/n = 7/n, so:

(7/n)[Sigma i = 0 to n](ln(7/n)/(7/n))

I feel like this isn't right for some reason.

2. Determine a region whose area is equal to:

lim as n->infinity of (Sigma i = 0 to n)(4pi/4n)(tan (i*pi/4n))

pi/4n is constant so that is the change in x.

Don't know how to go any further here...

And help appreciated.

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# Unsure about these two

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