Calculating Area Under Curve with Trapezium Rule

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henryc09
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Homework Statement


A modified form of the trapezium rule for calculating the area under a curve makes use of strips
of varying width: by using narrower strips where the gradient varies more rapidly, better
accuracy can be achieved. Create a function to perform the integral

[tex]\int1/x dx[/tex] between 1 and 101

using the trapezium rule with strips that increase geometrically in width, such that,

[tex]\Delta[/tex]Xn=rn-1[tex]\Delta[/tex]X1 where [tex]\Delta[/tex]Xn is the width of the nth strip and r is a constant (which is an
input to the function).
Choose the value of Δx1 to give a total of 100 strips for any value of r (hint: you will need the
formula for the sum of a geometric progression to calculate Δx1).

Homework Equations


b00394bd694cf4efdc248ce10ba6d29b.png

The Attempt at a Solution



Not sure where to start really, I mean a simple application of the trapezium rule to it would be simple enough. Define a vector x=[1:1:101] and then y=1./x and integral=trapz(x,y) or something along those lines (I don't have access to MATLAB from home so I couldn't be sure). Any point in the right direction would be much appreciated.
 
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