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1.6.2 Numerical Sums, Products and Integrals
NSum[f, {i,  , Infinity}] | numerical approximation to  | NProduct[f, {i,  , Infinity}] | numerical approximation to  | NIntegrate[f, {x,  ,  }] | numerical approximation to  |
NIntegrate[f, {x,  ,  }, {y,  ,  }]
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Numerical sums, products and integrals. Here is a numerical approximation to  . | |
In[1]:=
NSum[1/i^3, {i, 1, Infinity}]
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Out[1]=
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| NIntegrate can handle singularities at the end points of the integration region. | |
In[2]:=
NIntegrate[1/Sqrt[x (1-x)], {x, 0, 1}]
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Out[2]=
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| You can do numerical integrals over infinite regions. | |
In[3]:=
NIntegrate[Exp[-x^2], {x, -Infinity, Infinity}]
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Out[3]=
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| Here is a double integral over a triangular domain. Note the order in which the variables are given. | |
In[4]:=
NIntegrate[ Sin[x y], {x, 0, 1}, {y, 0, x} ]
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Out[4]=
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