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matlabmathsymbolic-math

Symbolic limit calculation, numeric value desired

I am trying to calculate a limit operation of a function inside. Here is what I did: 

x = 0;
f = (cos(x)*cos(h/2)*sin(h/2))/(h/2) - (sin(x)*sin(h/2)*sin(h/2))/(h/2);
limit(f,h,0)
ans =
1

limit(f,h,1)
ans =
2*cos(1/2)*sin(1/2)

I want to see what the numeric value of 2*cos(1/2)*sin(1/2) is. How do I obtain this value?

Solution

  • You can use double to evaluate the final expression:

    double(limit(f,h,1))
ans =
    0.8415

    limit is a symbolic function, so it outputs symbolic functions. You can use double (or single or whatever numeric type you want) to convert to a number.