Lösung 1.3:1c

Aus Online Mathematik Brückenkurs 2

(Unterschied zwischen Versionen)
Wechseln zu: Navigation, Suche
K
Zeile 1: Zeile 1:
-
The function has zero derivative at three points,
+
The function has zero derivative at three points, <math>x=a</math>, <math>x=b</math> and <math>x=c</math> (see picture below), which are therefore the critical points of the function.
-
<math>x=a</math>,
+
-
<math>x=b</math>and
+
-
<math>x=c</math>
+
-
(see picture below), which are therefore the critical points of the function.
+
[[Image:1_3_1_c1.gif|center]]
[[Image:1_3_1_c1.gif|center]]
-
The point
+
The point <math>x=b</math> is an inflexion point because the derivative is positive in a neighbourhood both to the left and right.
-
<math>x=b</math>
+
-
is an inflexion point because the derivative is positive in a neighbourhood both the left and right.
+
-
At the left endpoint of the interval of definition and at
+
At the left endpoint of the interval of definition and at <math>x=c</math>, the function has local maximum points , because the function takes lower values at all points in the vicinity of these points. At the point <math>x=a</math> and the right endpoint, the function has local minimum points.
-
<math>x=c</math>, the function has local maximum points , because the function takes lower values at all points in the vicinity of these points. At the point
+
-
<math>x=a</math>
+
-
and the right endpoint, the function has local minimum points.
+
-
 
+
-
Also, we see that
+
-
<math>x=c</math>
+
-
is a global maximum (the function takes its largest value there) and the right endpoint is a global minimum.
+
 +
Also, we see that <math>x=c</math> is a global maximum (the function takes its largest value there) and the right endpoint is a global minimum.
[[Image:1_3_1_c2.gif|center]]
[[Image:1_3_1_c2.gif|center]]
-
Between the left endpoint and
+
Between the left endpoint and <math>x=a</math>, as well as between <math>x=c</math>
-
<math>x=a</math>, as well as between
+
and the right endpoint, the function is strictly decreasing (the larger <math>x</math> is, the smaller <math>f(x)</math> becomes), whilst the function is strictly increasing between <math>x=a</math> and <math>x=c</math> (the graph flattens out at <math>x=b</math>, but it isn't constant there).
-
<math>x=c</math>
+
-
and the right endpoint, the function is strictly decreasing (the larger
+
-
<math>x</math>
+
-
is, the smaller
+
-
<math>f\left( x \right)</math>
+
-
becomes), whilst the function is strictly increasing between
+
-
<math>x=a</math>
+
-
and x=c (the graph flattens out at
+
-
<math>x=b</math>, but it isn't constant there).
+
-
 
+
[[Image:1_3_1_c3.gif|center]]
[[Image:1_3_1_c3.gif|center]]

Version vom 12:03, 17. Okt. 2008

The function has zero derivative at three points, \displaystyle x=a, \displaystyle x=b and \displaystyle x=c (see picture below), which are therefore the critical points of the function.

The point \displaystyle x=b is an inflexion point because the derivative is positive in a neighbourhood both to the left and right.

At the left endpoint of the interval of definition and at \displaystyle x=c, the function has local maximum points , because the function takes lower values at all points in the vicinity of these points. At the point \displaystyle x=a and the right endpoint, the function has local minimum points.

Also, we see that \displaystyle x=c is a global maximum (the function takes its largest value there) and the right endpoint is a global minimum.

Between the left endpoint and \displaystyle x=a, as well as between \displaystyle x=c and the right endpoint, the function is strictly decreasing (the larger \displaystyle x is, the smaller \displaystyle f(x) becomes), whilst the function is strictly increasing between \displaystyle x=a and \displaystyle x=c (the graph flattens out at \displaystyle x=b, but it isn't constant there).