2.16¶

; Explain, in general, why equivalent algebraic expressions 
; may lead to different answers. Can you devise an 
; interval-arithmetic package that does not have this shortcoming, 
; or is this task impossible? (Warning: This problem is very difficult.)

; Answer
; This seems to include a lot of derivation from interval systems. Although,
; from what I feel, the task seems impossible. i.e. we can not devise
; a package having no shortcoming