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111 lines
1.1 KiB
111 lines
1.1 KiB
2 years ago
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Exercise 1.43: If
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f
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is a numerical function
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and
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n
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is a positive integer, then we can form the
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n
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th
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repeated
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application of
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f
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, which is defined to be the function whose value at
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x
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is
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f
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(
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f
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(
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…
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(
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f
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(
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x
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)
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)
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…
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)
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)
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. For example, if
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f
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is the
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function
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x
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↦
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x
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+
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1
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, then the
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n
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th
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repeated application of
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f
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is
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the function
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x
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↦
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x
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+
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n
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. If
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f
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is the operation of squaring a
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number, then the
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n
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th
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repeated application of
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f
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is the function that
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raises its argument to the
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2
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n
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-th
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power. Write a procedure that takes as
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inputs a procedure that computes
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f
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and a positive integer
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n
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and returns
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the procedure that computes the
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n
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th
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repeated application of
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f
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. Your
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procedure should be able to be used as follows:
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((repeated square 2) 5)
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625
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Hint: You may find it convenient to use compose from Exercise 1.42.
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