Download Algebra [Lecture notes] by Burkhard Külshammer PDF

By Burkhard Külshammer

Show description

Read or Download Algebra [Lecture notes] PDF

Similar elementary books

Riddles of the sphinx, and other mathematical puzzle tales

Martin Gardner starts off Riddles with questions about splitting up polygons into prescribed shapes and he ends this booklet with a suggestion of a prize of $100 for the 1st individual to ship him a three x# magic sq. including consecutive primes. basically Gardner might healthy such a lot of diversified and tantalizing difficulties into one publication.

Beginning and Intermediate Algebra: An Integrated Approach

Get the grade you will want in algebra with Gustafson and Frisk's starting AND INTERMEDIATE ALGEBRA! Written with you in brain, the authors supply transparent, no-nonsense reasons to help you examine tough innovations very easily. arrange for tests with various assets positioned on-line and during the textual content akin to on-line tutoring, bankruptcy Summaries, Self-Checks, preparing routines, and Vocabulary and proposal difficulties.

Elementary Algebra

Straight forward ALGEBRA deals a pragmatic method of the examine of starting algebra techniques, in line with the desires of ultra-modern scholar. The authors position detailed emphasis at the labored examples in each one part, treating them because the basic technique of guide, considering the fact that scholars depend so seriously on examples to accomplish assignments.

Additional info for Algebra [Lecture notes]

Sample text

Satz: Sei R Integrit¨ atsbereich. Dann definiert man eine Aquivalenzrelation ∼ auf R × (R \ {0}) durch (a, b) ∼ (a′ , b′ ) :⇔ ab′ = a′ b. ¨ Bezeichnet man f¨ ur a, b ∈ R mit b = 0 die Aquivalenzklasse von (a, b) mit [a, b], so ist Q(R) := {[a, b] : a, b ∈ R, b = 0} ein K¨ orper mit [a, b] + [c, d] := [ad + bc, bd], [a, b][c, d] := [ac, bd]. Nullelement in Q(R) ist [0, 1], Einselement [1, 1], und es gilt: −[a, b] = [−a, b], [a, b]−1 = [b, a]. Die Abbildung ι : R → Q(R), a → [a, 1] ist ein unit¨ arer Monomorphismus, und f¨ ur a, b ∈ R mit b = 0 ist [a, b] = ι(a)ι(b)−1 .

Beweis: Offenbar ist f ein Homomorphismus und ker(f ) = I1 ∩ . . ∩ In . Homomorphiesatz: R/I1 ∩ . . ∩ In ∼ = f (R) ⊆ R/I1 × . . × R/In . Sei also Ii + Ij = R f¨ ur i = j. W¨ ahle aij ∈ Ii , bij ∈ Ij mit 1 = aij + bij (i = j). Dann ist sj := k=j akj ∈ Ii f¨ ur i = j und sj + Ij = k=j (1 − bkj ) + Ij = 1 + Ij . Sind r1 , . . , rn ∈ R n und ist r := j=1 rj sj , so ist n rj sj + Ii = ri si + Ii = ri + Ii r + Ii = f¨ ur i = 1, . . h. f (r) = (r1 + I1 , . . , rn + In ). Daher ist f surjektiv, und R/I1 ∩ .

Pn = s1 . . sk q1 . . ql mit irreduziblen Elementen r1 , . . , rm , s1 . . , sk in R und primitiven Polynomen p1 , . . , pn , q1 , . . , ql in R[X], die irreduzibel in K[X] sind. Da p1 . . pn und q1 . . 1 ein u ∈ R× mit r1 . . rm = s1 . . sk u−1 , p1 . . pn = q1 . . ql u. Da R faktoriell ist, muß k = m und ri zu si assoziiert f¨ ur i = 1, . . , k bei geeigneter Numerierung sein. Da K[X] faktoriell ist, muß l = n und pi zu qi f¨ ur i = 1, . . , l bei geeigneter Numerierung in K[X] assoziiert sein.

Download PDF sample

Rated 4.18 of 5 – based on 41 votes