Exercise 15.  Find the linear transformations  [Graphics:Images/ComplexFunLinearModHome_gr_396.gif]  that satisfy the following conditions.  

15 (c).  The triangle with vertices  [Graphics:Images/ComplexFunLinearModHome_gr_443.gif]  maps onto the triangle with vertices  [Graphics:Images/ComplexFunLinearModHome_gr_444.gif],  respectively.

Solution 15 (c).

See text and/or instructor's solution manual.

Write out the three equations to solve:  [Graphics:../Images/ComplexFunLinearModHome_gr_445.gif]  for  [Graphics:../Images/ComplexFunLinearModHome_gr_446.gif].  

        [Graphics:../Images/ComplexFunLinearModHome_gr_447.gif]    

Solve the above system of equations.  Subtract equation 1 from equations 2 and 3.

        [Graphics:../Images/ComplexFunLinearModHome_gr_448.gif]    

The system is consistent (equation 3 is equivalent to equation 2) and we see that  [Graphics:../Images/ComplexFunLinearModHome_gr_449.gif].  Use this fact to and solve for  B.

        [Graphics:../Images/ComplexFunLinearModHome_gr_450.gif]    

The linear transformations is

          [Graphics:../Images/ComplexFunLinearModHome_gr_451.gif].  

          

[Graphics:../Images/ComplexFunLinearModHome_gr_452.gif]          [Graphics:../Images/ComplexFunLinearModHome_gr_453.gif]

  

The transformation   [Graphics:../Images/ComplexFunLinearModHome_gr_454.gif]  maps the triangle with vertices  [Graphics:../Images/ComplexFunLinearModHome_gr_455.gif]
onto the triangle with vertices  [Graphics:../Images/ComplexFunLinearModHome_gr_456.gif],  respectively.

We are done.   

Aside.  We can let Mathematica double check our work.

[Graphics:../Images/ComplexFunLinearModHome_gr_457.gif]
[Graphics:../Images/ComplexFunLinearModHome_gr_458.gif]
[Graphics:../Images/ComplexFunLinearModHome_gr_459.gif]
[Graphics:../Images/ComplexFunLinearModHome_gr_460.gif]
[Graphics:../Images/ComplexFunLinearModHome_gr_461.gif]
[Graphics:../Images/ComplexFunLinearModHome_gr_462.gif]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

This solution is complements of the authors.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(c) 2008 John H. Mathews, Russell W. Howell