4. The following polynomial is irreducible in Q[x]: m(x) = x² - 2x²-1 € Q[x] Let's consider the ideal I = (m(x)), and the quotient ring F = = Q[x]/I. (a) Explain why F is a field. (b) Consider the element a = x + I of F. Show that a is a root of m(x). In other words, show that is zero in the ring F. a4-2a2-1=0

Elements Of Modern Algebra
8th Edition
ISBN:9781285463230
Author:Gilbert, Linda, Jimmie
Publisher:Gilbert, Linda, Jimmie
Chapter8: Polynomials
Section8.6: Algebraic Extensions Of A Field
Problem 13E
icon
Related questions
Question

Thank you

4. The following polynomial is irreducible in Q[x]:
m(x) = x² — 2x² – 1 € Q[x]
Let's consider the ideal I = (m(x)), and the quotient ring F = Q[x]/I.
(a) Explain why F is a field.
(b) Consider the element a = x + I of F. Show that a is a root of m(x). In other words, show that
is zero in the ring F.
a42a2-10
Remark: Question 4 shows that we can construct a field extension QC F where the polynomial m(x) has a
root: we define F = Q[x]/[m(x)). The same construction works in much greater generality.
Transcribed Image Text:4. The following polynomial is irreducible in Q[x]: m(x) = x² — 2x² – 1 € Q[x] Let's consider the ideal I = (m(x)), and the quotient ring F = Q[x]/I. (a) Explain why F is a field. (b) Consider the element a = x + I of F. Show that a is a root of m(x). In other words, show that is zero in the ring F. a42a2-10 Remark: Question 4 shows that we can construct a field extension QC F where the polynomial m(x) has a root: we define F = Q[x]/[m(x)). The same construction works in much greater generality.
Expert Solution
steps

Step by step

Solved in 4 steps with 3 images

Blurred answer
Recommended textbooks for you
Elements Of Modern Algebra
Elements Of Modern Algebra
Algebra
ISBN:
9781285463230
Author:
Gilbert, Linda, Jimmie
Publisher:
Cengage Learning,
Algebra & Trigonometry with Analytic Geometry
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:
9781133382119
Author:
Swokowski
Publisher:
Cengage
College Algebra
College Algebra
Algebra
ISBN:
9781337282291
Author:
Ron Larson
Publisher:
Cengage Learning
Trigonometry (MindTap Course List)
Trigonometry (MindTap Course List)
Trigonometry
ISBN:
9781337278461
Author:
Ron Larson
Publisher:
Cengage Learning