solution to 3.60. Untested. Skipping 3.61 and 3.62.

diff --git a/src/sicp/ex3_60.rkt b/src/sicp/ex3_60.rkt
new file mode 100644 (file)
index 0000000..1110c28
--- /dev/null
+++ b/src/sicp/ex3_60.rkt
@@ -0,0 +1,10 @@
+#lang racket
+
+(define (mul-series s1 s2)
+  (cons-stream (* (stream-car s1)
+                  (stream-car s2))
+               (add-streams (scale-stream (stream-cdr s1) (stream-car s2))
+                            (add-streams 
+                             (scale-stream (stream-cdr s2) (stream-car s1))
+                             (mul-series (stream-cdr s1) 
+                                         (stream-cdr s2))))))
\ No newline at end of file