•Second 2×2 Example

In[1]:=

A = (3 -2) ; -1 0

In[2]:=

p[λ_] = Det[A - λ I _ 2]

Out[2]=

-2 - 3 λ + λ^2

In[3]:=

Factor[p[λ]]

Out[3]=

-2 - 3 λ + λ^2

In[4]:=

Solve[p[λ] == 0, λ]

Out[4]=

{{λ -> 1/2 (3 - 17^(1/2))}, {λ -> 1/2 (3 + 17^(1/2))}}

In[5]:=

N[Solve[p[λ] == 0, λ]]

Out[5]=

{{λ -> -0.5615528128088303`}, {λ -> 3.5615528128088303`}}

Converted by Mathematica  (November 21, 2002)