
PreCalculus PreCalculus Math Forum 
 LinkBack  Thread Tools  Display Modes 
November 13th, 2016, 01:20 PM  #1 
Member Joined: Nov 2016 From: Ireland Posts: 71 Thanks: 2  Another functional disfunction
If r(t) = 2t+3 and s(t) = 7t^2  t find : s(r(t)) s(r(t)) = s(2t + 3) = 7(2t + 3)^2 − (2t + 3) <<<{Where is this guy coming from?} = 7(4t^2 + 12t + 9) − (2t + 3) = (28t^2 + 84t + 63) − (2t + 3) = 28t^2 + 82t + 60 I can understand the first (2t + 3)^2 but surely that should cover the function s. Why the need for the 2t + 3? Last edited by Kevineamon; November 13th, 2016 at 01:23 PM. 
November 13th, 2016, 01:53 PM  #2 
Global Moderator Joined: Dec 2006 Posts: 18,145 Thanks: 1418 
Each "t" in "s(t) = 7t^2  t" is to be replaced with "2t + 3".

November 13th, 2016, 02:03 PM  #3 
Member Joined: Nov 2016 From: Ireland Posts: 71 Thanks: 2 
Ahhh well there we go. Thanks Skipjack.


Tags 
disfunction, functional 
Thread Tools  
Display Modes  

Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Functional DE  neelmodi  Differential Equations  1  February 11th, 2016 08:01 PM 
constrained functional minimization  functional linear in the derivatives  el keke  Calculus  0  October 31st, 2014 01:07 PM 
functional equation  nukem4111  Real Analysis  1  September 16th, 2013 04:44 AM 
Functional equation  arnold  Algebra  1  October 13th, 2011 05:23 AM 
Functional equation  georgij  Algebra  3  October 9th, 2011 03:55 AM 