Update instructions.md (#624)

Fixed typos in instructions

exercises/concept/coordinate-transformation/.docs/instructions.md

@@ -50,9 +50,9 @@ Implement the `memoize-transform` function. It takes a function to _memoize_, th
 (def triple-scale (scale2d 3 3))
 (def memoized-scale (memoize-transform triple-scale))
 
-(memoizedScale 4 3)
+(memoized-scale 4 3)
 ;; => [12, 9], this is computed since it hasn't been computed before for the arguments
 
-(memoizedScale 4 3)
+(memoized-scale 4 3)
 ;; => [12, 9], this is remembered, since it was computed already
-```
+```