Aufgabe 1
Wx, yeR:4xy (x y)2 2(x2 x2)
=
(i) 2.2. +
-
+
4x x = (x y)=
+
2(x2 y2) +
(4xy (x y)2 y)2 2(x2 y2)
=
1 =
+
(x +
=
+
1. 2.2. 4xy = (x+ y)2
4xx (x y)2 +
1=>
4xy x2 2xy = +
y2
+
2
1
30 y2
=
x 2xy
- +
1 10
=
(X -
y)2
=>
wahr, da Quadrate immer 10 sind. - 0=(X -
y)2
2. 2.2. (x y) 2(x y2) 2
24xy (x y12 (x y)2 z(x y))
=
+
+ +
+ +
- = =
(x y)2
+
2(x
=
+y2) c
24xy
=
(x
= +
y12 2(x2
=
y2)
+
c 3 =
x2 +
2xy y2
+
= 2x2 2y2 +
x2xy x yz
*
=
1 =
+
=7 0 x2
=
-
2xy y2
+
=S 0 (X y)2
= -
=>
wahr, siehe 1.
(ii) 2.2. Fx, yER:1x1+1y) = (x y)
+ +
1x -
y)
|x1 +
(y) (x
= +
y)
+
1x -
y)
Fall 1:Sei oBdA 0 y cx Fall 3:seiOBdA x <y10
|x 1y) + x y
+
x
+
-
y |x1 14)
+
=1x x) 1x +
+ -
x)
1 3 x (x y) (x x)
=
yx
-
-
2x
- - -
+
=
c 7 =
x y
+
A
wahr, da yx y
=
1 x x y x
Y
- -
- -
- +
=( -x = 2x
y
- -
Fall 2:sei oBdA ycOCX
1 =
3x = 2x
y
+
|x1 (y) =
|x x) 1x
+
+
+
-
y)
wahr,
~ da yx.
1 x - y =
(x x)
+
x
+ -
x
1 3
=
0 = (x x)
+ *Alle Falle bewiesen.
=>
IXy=IXTYHX-X XX,YER.
Aussage, da Betrag
*Wahre immer?O ist.
, Aufgabe 2
(i) Ac [ 55 x, 5 1)w(x 1,55 1]
=
- -
- -
-
-
Beweis:
Sei xeA, 11x2 2x 4
=
+
(2x+2x 1 5 +
=
2x 1 5
,
+
=
2 x
x -
+ 15 55 -
x xx
= +
-
E
1 3 =
8 -
1x 15 -
7 -
15 12xc
- -
x 1 -
1 x-
=
[ 5 1, -
- -
z -
)v(1 x, x] -
-
(i) Az I,0)
=
Beweis:
SeixtAzc => 11X 11-21= X+
1 7 x (x x) z=x
=
-
-
+
=
c 3 = -
x 2 |x (1x
+
+
1)
+
- x 2
+
(2) -
x 2
+
x
=
7vx
+
-
22x 11 +
-
x -
2x 11
+ x 2
+
1 x x
=
1
-
2x
1
-
-
X
-
c - =
x [2,0)
=
Wx, yeR:4xy (x y)2 2(x2 x2)
=
(i) 2.2. +
-
+
4x x = (x y)=
+
2(x2 y2) +
(4xy (x y)2 y)2 2(x2 y2)
=
1 =
+
(x +
=
+
1. 2.2. 4xy = (x+ y)2
4xx (x y)2 +
1=>
4xy x2 2xy = +
y2
+
2
1
30 y2
=
x 2xy
- +
1 10
=
(X -
y)2
=>
wahr, da Quadrate immer 10 sind. - 0=(X -
y)2
2. 2.2. (x y) 2(x y2) 2
24xy (x y12 (x y)2 z(x y))
=
+
+ +
+ +
- = =
(x y)2
+
2(x
=
+y2) c
24xy
=
(x
= +
y12 2(x2
=
y2)
+
c 3 =
x2 +
2xy y2
+
= 2x2 2y2 +
x2xy x yz
*
=
1 =
+
=7 0 x2
=
-
2xy y2
+
=S 0 (X y)2
= -
=>
wahr, siehe 1.
(ii) 2.2. Fx, yER:1x1+1y) = (x y)
+ +
1x -
y)
|x1 +
(y) (x
= +
y)
+
1x -
y)
Fall 1:Sei oBdA 0 y cx Fall 3:seiOBdA x <y10
|x 1y) + x y
+
x
+
-
y |x1 14)
+
=1x x) 1x +
+ -
x)
1 3 x (x y) (x x)
=
yx
-
-
2x
- - -
+
=
c 7 =
x y
+
A
wahr, da yx y
=
1 x x y x
Y
- -
- -
- +
=( -x = 2x
y
- -
Fall 2:sei oBdA ycOCX
1 =
3x = 2x
y
+
|x1 (y) =
|x x) 1x
+
+
+
-
y)
wahr,
~ da yx.
1 x - y =
(x x)
+
x
+ -
x
1 3
=
0 = (x x)
+ *Alle Falle bewiesen.
=>
IXy=IXTYHX-X XX,YER.
Aussage, da Betrag
*Wahre immer?O ist.
, Aufgabe 2
(i) Ac [ 55 x, 5 1)w(x 1,55 1]
=
- -
- -
-
-
Beweis:
Sei xeA, 11x2 2x 4
=
+
(2x+2x 1 5 +
=
2x 1 5
,
+
=
2 x
x -
+ 15 55 -
x xx
= +
-
E
1 3 =
8 -
1x 15 -
7 -
15 12xc
- -
x 1 -
1 x-
=
[ 5 1, -
- -
z -
)v(1 x, x] -
-
(i) Az I,0)
=
Beweis:
SeixtAzc => 11X 11-21= X+
1 7 x (x x) z=x
=
-
-
+
=
c 3 = -
x 2 |x (1x
+
+
1)
+
- x 2
+
(2) -
x 2
+
x
=
7vx
+
-
22x 11 +
-
x -
2x 11
+ x 2
+
1 x x
=
1
-
2x
1
-
-
X
-
c - =
x [2,0)
=