User:Annlex/Mathproject
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CURVE SKETCHING
f(x)=x4+4x3+6x2+4x
-Roots:
0=x4+4x3+6x2+4x
0=x(x3+4x2+6x+4)
x1=0
x3+4x2+6x+4=0
x2=-2 (erraten)
Polynomdivision:
(x3+4x2+6x+4):(x+2)= x2+2x+2
-(x3+2x2)
--------
2x2+6x
-(2x2+4x)
--------
2x+4
-(2x+4)
--------
000
x2+2x+2=0
x1,2=
Roots:NS1(0/0),NS2(-2/0)
-1. Derivation:
f´(x)=4x3+12x2+12x+4
0=4x3+12x2+12x+4
x1= - 1 (erraten)
(4x3+12x2+12x+4) : (x+1) = 4x2+8x+4
-(4x3+4x2)
---------
8x2+12x
-(8x2+8x)
--------
4x+4
-(4x+4)
-------
000
quadratic equation:
4x2+8x+4=0
4(x2+2x+1)=0
4(x+1)2=0
x1=x2=x3=-1 (tripple root)
-2. Derivation:
f´´(x)=12x+24x+12
f´´(-1)=12-24+12=0 (no solution)
f´(0)=4 (positiv gradient)
-TIP(-1/-1) (absolute minimum)
-Wf=[-1;+unendlich[
-Df=[-unendlich;+unentlich[
-There is no symmrtry to the koordinate plane.
general procedure:
f(x):
-roots: find out when the y-value is zero
f(x)=0