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Unformatted text preview: A = P / n;
A = P * (i .* (i + 1).^n) ./ ((i + 1).^n ‐ 1);
end 5 1/18/2010 Problem: Find all of the points that satisfy both y = x2‐17x+60 and y = 50sin(x/2)
(i.e. find all of the intersections of the curves defined by these equations).
Step 1: Plot the two curves.
>> f1 = @(x) 50 * sin(0.5 * x);
>> f2 = @(x) x.^2 ‐ 17 * x + 60;
>> x = linspace (0, 20, 100);
>> y1 = f1(x); y2 = f2(x);
>> plot (x, y1, 'r', x, y2, 'b')
>> grid on
The plot function will accept more than one pair of x and y vectors. This allows multiple plots to be placed on the same graph. Each pair of vectors may be followed by a string cntaining plotting options. Some of the permitted characters are:
colour: ‘r’ = red, ‘b’ = blue, ‘k’ = black, ‘g’ = green
line style: ‘‐’ = solid, ‘:’ = dotted, ‘‐‐’ = dashed, ‘‐.’ = dash dot
data point markers: ‘x’ = crosses, ‘o’ = circles
Options may be combined (e.g. ‘r:x’ gives a dotted red plot with a crosses) 6 1/18/2010 Note: The hold command is another way of placing multiple plots on the same graph.
>> plot (x, y1, 'r‘)
>> hold on
>> plot (x, y2, 'b')
>> hold off % be careful ‐ hold for a figure stays in effect until it is turned off
>> grid on
Step 2: Define the function for root finding (and perhaps plot it)
>> f = @(x) f1(x) ‐ f2(x);
>> figure (2)
>> fplot (f, [0 20])
>> grid on;
Step 3: Find the roots:
>> x1 = fzero(f, [0 2]);
>> x2 = fzero(f, [6 8]);
>> x3 = fzero(f, [12 14]);
>> x4 = fzero(f, [16 18]); 7...
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This note was uploaded on 09/13/2013 for the course ECOR 2606 taught by Professor Goheen during the Fall '10 term at Carleton CA.
- Fall '10