E e7aine New Member Joined Feb 13, 2006 Messages 6 Location Sydney Gender Female HSC 2006 Apr 19, 2006 #1 Explain why all solutions of the equation 3sinx = x - 1 must lie between x=-2 and x=4.
T Templar P vs NP Joined Aug 11, 2004 Messages 1,972 Gender Male HSC 2004 Apr 19, 2006 #2 We know that -1<=sinx<=1, so -3<=3sinx<=3. For x<-2, RHS<-3 therefore equality will not exist. Similarly for x>4, RHS>3.
We know that -1<=sinx<=1, so -3<=3sinx<=3. For x<-2, RHS<-3 therefore equality will not exist. Similarly for x>4, RHS>3.
