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// PG (261)
// Example 1
deff('[y]=f(x)','y=x^(7/2)')
deff('[y]=fp(x)','y=3.5*x^(5/2)')
deff('[y]=fpp(x)','y=8.75*x^(3/2)')
deff('[y]=fppp(x)','y=(105*sqrt(x))/8')
deff('[y]=fpppp(x)','y=(105*x^(-0.5))/16')
x0=0;
xn=1;
x=x0:xn;
// True value
I = integrate('x^(7/2)','x',x0,xn)
// Using Trapezoidal rule
n=2;
h=(xn-x0)/n;
I1 = (xn-x0) * (f(x0)+f(xn)) /4;
E1 = -h^2 * (fp(xn)-fp(x0)) /12 // Error
n=4;
h=(xn-x0)/n;
I2 = (xn-x0) * (f(x0)+f(xn)) /4;
E2 = -h^2 * (fp(xn)-fp(x0)) /12 // Error
// Using Simpson's rule
N=2;
h=(xn-x0)/N;
x1=x0+h;
x2=x0+2*h;
I1 = h*(f(x0)+4*f(x1)+f(x2))/3
E1 = -h^4*(xn-x0)*fpppp(0.5)/180
N=4;
h=(xn-x0)/N;
x1=x0+h;
x2=x0+2*h;
x3=x0+3*h;
x4=x0+4*h;
I2 = h*(f(x0)+4*f(x1)+2*f(x2)+4*f(x3)+f(x4))/3
E2 = -h^4*(xn-x0)*fpppp(0.5)/180
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