SICP Exercise 2.34 horner-eval

Exercise 2.34.  Evaluating a polynomial in x at a given value of x can be formulated as an accumulation. We evaluate the polynomial


using a well-known algorithm called Horner's rule, which structures the computation as


In other words, we start with an, multiply by x, add an-1, multiply by x, and so on, until we reach a0.16 Fill in the following template to produce a procedure that evaluates a polynomial using Horner's rule. Assume that the coefficients of the polynomial are arranged in a sequence, from a0 through an.

(define (horner-eval x coefficient-sequence)
  (accumulate (lambda (this-coeff higher-terms) <??>)
              0
              coefficient-sequence))

For example, to compute 1 + 3x + 5x3 + x5 at x = 2 you would evaluate

(horner-eval 2 (list 1 3 0 5 0 1))

 SOLUTION
The code and tests are here.

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