Finding the Area Bounded by Curves | Quick Solution

BOAS
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Hello,

quick question really.

Homework Statement



Find the area bound by the x axis, x = 1, x = 4 and y = 2/x

Homework Equations


The Attempt at a Solution



Representing this graphically, the question is equivalent to performing the definite integral of y = 2/x from 1 to 4. Right?

Which would result in the area being equal to 2 ln(4)

It seems painfully obvious but this question has made me doubt myself so I wanted to check I haven't missed anything obvious... i.e is there any reason to do the longhand of subtracting the smaller areas from the larger ones.

Thanks,

BOAS
 
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You are absolutely correct. I see no reason to put anything more than the integral you described. For any positive, integrable function, the area between the curve and the x-axis is equal to the definite integral of the function over the region concerned.
 
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