SICP Exercise 1.39 Lambert's Formula

Exercise 1.39.  A continued fraction representation of the tangent function was published in 1770 by the German mathematician J.H. Lambert:


where x is in radians. Define a procedure (tan-cf x k) that computes an approximation to the tangent function based on Lambert's formula. K specifies the number of terms to compute, as in exercise 1.37.

SOLUTION

 The code and tests are here.

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