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1.6.2 Numerical Sums, Products and Integrals


Numerical sums, products and integrals.




  • Here is a numerical approximation to


    .
  • In[1]:= NSum[1/i^3, {i, 1, Infinity}]

    Out[1]=

  • NIntegrate can handle singularities at the end points of the integration region.
  • In[2]:= NIntegrate[1/Sqrt[x (1-x)], {x, 0, 1}]

    Out[2]=

  • You can do numerical integrals over infinite regions.
  • In[3]:= NIntegrate[Exp[-x^2], {x, -Infinity, Infinity}]

    Out[3]=

  • 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} ]

    Out[4]=