<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content="text/html; charset=gb2312" http-equiv=Content-Type> <META name=GENERATOR content="MSHTML 9.00.8112.16457"></HEAD> <BODY> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN class=223234919-12012013>Assuming Jamel does a self study.</SPAN></FONT></DIV> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN class=223234919-12012013>I think Jamel ment <FONT color=#000000 size=3 face="Times New Roman">(/ (+ (* n n) 300) (* 13 n)).</FONT></SPAN></FONT></DIV> <DIV dir=ltr align=left><FONT face="Times New Roman"><SPAN class=223234919-12012013>Grant, with your definition:</SPAN></FONT></DIV> <DIV dir=ltr align=left><FONT face="Times New Roman"><SPAN class=223234919-12012013>(define (f n) ( +  ( * n 2 ) 300))</SPAN></FONT></DIV> <DIV dir=ltr align=left><FONT face="Times New Roman"><SPAN class=223234919-12012013>(f 5) -> 310</SPAN></FONT></DIV> <DIV dir=ltr align=left><FONT face="Times New Roman"><SPAN class=223234919-12012013>As Jamel is expecting 325, I assume n*2 is ment as an exponentiation.</SPAN></FONT></DIV> <DIV dir=ltr align=left><FONT face="Times New Roman"><SPAN class=223234919-12012013></SPAN></FONT> </DIV> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial><SPAN class=223234919-12012013>There are many ways to write this down, for example:</SPAN></FONT></DIV> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial></FONT> </DIV> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial>(define (f n) (/ (+ (expt n 2) 300) (* 13 n)))</FONT></DIV> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial>(define (<SPAN class=223234919-12012013>f</SPAN> n) (/ (+ (* n n) 300) 13 n))</FONT></DIV> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial>(define (f n) (/ (+ (expt n 2) 300) 13 n))</FONT></DIV> <DIV dir=ltr align=left><FONT color=#0000ff size=2 face=Arial></FONT> </DIV> <DIV dir=ltr align=left><SPAN class=223234919-12012013><FONT color=#0000ff size=2 face=Arial>Jos</FONT></SPAN></DIV><BR> <DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left> <HR tabIndex=-1> <FONT size=2 face=Tahoma><B>From:</B> users-bounces@racket-lang.org [mailto:users-bounces@racket-lang.org] <B>On Behalf Of </B>Grant Rettke<BR><B>Sent:</B> s芍bado, 12 de enero de 2013 20:38<BR><B>To:</B> Jamel Hamani<BR><B>Cc:</B> users@racket-lang.org<BR><B>Subject:</B> Re: [racket] novice question about expressions<BR></FONT><BR></DIV> <DIV></DIV> <DIV>(/ (+ (* n 2) 300) (* 13 n))</DIV> <DIV><BR></DIV> <DIV> <DIV class=gmail_quote>On Fri, Jan 11, 2013 at 8:08 PM, Jamel Hamani <SPAN dir=ltr><<A href="mailto:jamelhamani@gmail.com" target=_blank>jamelhamani@gmail.com</A>></SPAN> wrote:<BR> <BLOCKQUOTE style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex" class=gmail_quote>(n*2+ 300) / (13n)</BLOCKQUOTE></DIV><BR><BR><BR clear=all> <DIV><BR></DIV>-- <BR>Grant Rettke | ACM, AMA, COG, IEEE<BR><A href="mailto:grettke@acm.org" target=_blank>grettke@acm.org</A> | <A href="http://www.wisdomandwonder.com/" target=_blank>http://www.wisdomandwonder.com/</A><BR>Wisdom begins in wonder.<BR>((竹 (x) (x x)) (竹 (x) (x x))) </DIV></BODY></HTML>