#LyX 2.3 created this file. For more info see http://www.lyx.org/ \lyxformat 544 \begin_document \begin_header \save_transient_properties true \origin unavailable \textclass article \begin_preamble \usepackage{siunitx} \usepackage{pgfplots} \usepackage{listings} \usepackage{multicol} \usepackage{amsmath} \sisetup{output-decimal-marker = {,}, quotient-mode=fraction, output-exponent-marker=\ensuremath{\mathrm{3}}} \DeclareMathOperator{\g}{g} \DeclareMathOperator{\sled}{sled} \DeclareMathOperator{\Aut}{Aut} \DeclareMathOperator{\Cir}{Cir} \DeclareMathOperator{\ecc}{ecc} \DeclareMathOperator{\rad}{rad} \DeclareMathOperator{\diam}{diam} \newcommand\euler{e} \end_preamble \use_default_options true \begin_modules enumitem \end_modules \maintain_unincluded_children false \language slovene \language_package default \inputencoding auto \fontencoding global \font_roman "default" "default" \font_sans "default" "default" \font_typewriter "default" "default" \font_math "auto" "auto" \font_default_family default \use_non_tex_fonts false \font_sc false \font_osf false \font_sf_scale 100 100 \font_tt_scale 100 100 \use_microtype false \use_dash_ligatures true \graphics xetex \default_output_format default \output_sync 0 \bibtex_command default \index_command default \paperfontsize default \spacing single \use_hyperref false \papersize default \use_geometry true \use_package amsmath 1 \use_package amssymb 1 \use_package cancel 1 \use_package esint 1 \use_package mathdots 1 \use_package mathtools 1 \use_package mhchem 1 \use_package stackrel 1 \use_package stmaryrd 1 \use_package undertilde 1 \cite_engine basic \cite_engine_type default \biblio_style plain \use_bibtopic false \use_indices false \paperorientation portrait \suppress_date false \justification false \use_refstyle 1 \use_minted 0 \index Index \shortcut idx \color #008000 \end_index \leftmargin 1cm \topmargin 1cm \rightmargin 1cm \bottommargin 2cm \headheight 1cm \headsep 1cm \footskip 1cm \secnumdepth 3 \tocdepth 3 \paragraph_separation indent \paragraph_indentation default \is_math_indent 0 \math_numbering_side default \quotes_style german \dynamic_quotes 0 \papercolumns 1 \papersides 1 \paperpagestyle default \tracking_changes false \output_changes false \html_math_output 0 \html_css_as_file 0 \html_be_strict false \end_header \begin_body \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout \backslash setlength{ \backslash columnseprule}{0.2pt} \backslash begin{multicols}{2} \end_layout \end_inset \end_layout \begin_layout Section Podmnožice v evklidskih prostorih \end_layout \begin_layout Standard \begin_inset Formula $A$ \end_inset zaprta, če \begin_inset Formula $\forall$ \end_inset zaporedje s členi v \begin_inset Formula $A:$ \end_inset vsa stekališča v \begin_inset Formula $A$ \end_inset . \end_layout \begin_layout Standard \begin_inset Formula $A$ \end_inset kompaktna, če \begin_inset Formula $\forall$ \end_inset zaporedje s členi v \begin_inset Formula $A$ \end_inset : \begin_inset Formula $\exists$ \end_inset stekališče v \begin_inset Formula $A$ \end_inset . \end_layout \begin_layout Standard \begin_inset Formula $f$ \end_inset je kompozitum zveznih \begin_inset Formula $\Rightarrow$ \end_inset \begin_inset Formula $f$ \end_inset zvezna \end_layout \begin_layout Standard za \begin_inset Formula $x\in\mathbb{R}^{k}$ \end_inset : \begin_inset Formula $\text{\left|\left|x\right|\right|\ensuremath{\coloneqq}}\sqrt{x_{1}^{2}+\cdots+x_{k}^{2}}$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $A\subseteq\mathbb{R}^{k}$ \end_inset omejena \begin_inset Formula $\Leftrightarrow\exists M\in\mathbb{R}\forall x\in A:\left|\left|x\right|\right|0:K\left(x,\varepsilon\right)\cup\left(A\setminus\left\{ x\right\} \right)\not=\emptyset$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $x\in\mathbb{R}^{k}$ \end_inset izolirana točka \begin_inset Formula $A\Leftrightarrow x$ \end_inset ni stekališče \begin_inset Formula $A$ \end_inset \end_layout \begin_layout Standard Zaporedje \begin_inset Formula $a_{n}:\mathbb{N}\to\mathbb{R}^{k}$ \end_inset konvergira proti \begin_inset Formula $a\in\mathbb{R}^{k}$ \end_inset kadar \begin_inset Formula $\forall\varepsilon>0\exists N\in\mathbb{N}\forall n>N:\left|\left|a_{n}-a\right|\right|<\varepsilon$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $s\in\mathbb{R}^{k}$ \end_inset stekališče zap. \begin_inset Formula $\Leftrightarrow$ \end_inset v \begin_inset Formula $\text{\ensuremath{\varepsilon}}-$ \end_inset okolici \begin_inset Formula $s$ \end_inset je \begin_inset Formula $\infty$ \end_inset mnogo členov \end_layout \begin_layout Standard Vsako omejeno zaporedje ima stekališče. \end_layout \begin_layout Section Funkcije več spremenljivk \end_layout \begin_layout Standard fja \begin_inset Formula $k$ \end_inset spremenljivk je preslikava \begin_inset Formula $f:D\subseteq\mathbb{R}^{k}\to\mathbb{R}$ \end_inset . \end_layout \begin_layout Standard \begin_inset Formula $L\in\mathbb{R}$ \end_inset je limita \begin_inset Formula $f:D\subseteq\text{\ensuremath{\mathbb{R}^{k}}}\to\mathbb{R}$ \end_inset v stekališču \begin_inset Formula $a\in D$ \end_inset , če \begin_inset Formula $\forall\varepsilon>0\exists\delta>0\forall x\in D\setminus\left\{ a\right\} :\left|\left|x-a\right|\right|<\delta\Rightarrow\left|f\left(x\right)-L\right|<\varepsilon$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $\lim_{x\to a}\left(f\oslash g\right)x=\lim_{x\to a}fx\oslash\lim_{x\to a}gx$ \end_inset , če obstajata. \begin_inset Formula $\oslash\in\left\{ +,-,\cdot\right\} $ \end_inset . \begin_inset Formula $\oslash$ \end_inset je lahko deljenje, kadar \begin_inset Formula $\lim_{x\to a}gx\not=0$ \end_inset . \end_layout \begin_layout Standard \begin_inset Formula $f$ \end_inset zvezna v \begin_inset Formula $a\Leftrightarrow\forall\varepsilon\exists\delta\forall x\in D:\left|\left|x-a\right|\right|<\delta\Rightarrow\left|fx-fa\right|<\varepsilon$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $f$ \end_inset zvezna \begin_inset Formula $\Leftrightarrow\forall a\in D:f$ \end_inset zvezna v \begin_inset Formula $a$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $f$ \end_inset zvezna v stekališču \begin_inset Formula $a\Leftrightarrow\lim_{x\to a}fx=fa$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $A\subseteq\mathbb{R}^{k}$ \end_inset kompaktna, \begin_inset Formula $f:A\to\mathbb{R}$ \end_inset zvezna \begin_inset Formula $\Rightarrow f$ \end_inset omejena in doseže maksimum in minimum (obstoj globalnega ekstrema). \end_layout \begin_layout Standard \begin_inset Formula $f,g$ \end_inset zv. \begin_inset Formula $\Rightarrow f\oslash g$ \end_inset zv. \begin_inset Formula $\oslash\in\left\{ +,-,\cdot,\circ\right\} ,\oslash=/\Leftrightarrow\forall x:gx\not=0$ \end_inset \end_layout \begin_layout Section Odvodi funkcij več spremenljivk \end_layout \begin_layout Standard \begin_inset Formula $f_{x_{i}}a$ \end_inset , \begin_inset Formula $i\in\left\{ 1..k\right\} $ \end_inset je odvod fje \begin_inset Formula $x_{i}\to f\left(a_{1},\dots,a_{i-1},x_{i},a_{i+1},\dots,a_{k}\right)$ \end_inset v točki \begin_inset Formula $a_{i}$ \end_inset . \begin_inset Formula $f_{x_{i}}a=\lim_{x_{i}\to a_{i}}\frac{f\left(a_{1},\dots,a_{i-1},x_{i},a_{i+1},\dots,a_{k}\right)-fa}{x_{i}-a_{i}}$ \end_inset \end_layout \begin_layout Standard Tang. ravn. v \begin_inset Formula $a=\left(b,c\right)$ \end_inset \begin_inset Formula $a=\left(b,c\right)$ \end_inset : \begin_inset Formula $z=fa+f_{x}a\cdot\left(x-b\right)+f_{y}a\cdot\left(y-c\right)$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $f$ \end_inset je odvedljiva v \begin_inset Formula $a\Leftrightarrow\lim_{h\to\left(0,0\right)}\frac{R_{a}\left(a+h\right)}{\left|\left|h\right|\right|}=0$ \end_inset , kjer je \begin_inset Formula $R_{a}\left(a+h\right)\coloneqq f\left(a+h\right)-fa-f_{x}\left(a\right)\cdot u+f_{y}\left(a\right)\cdot v$ \end_inset za \begin_inset Formula $h=\left(u,v\right)$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $dfa\coloneqq\left[f_{x_{1}}a\cdots f_{x_{k}}a\right]=\nabla fa,dfa\cdot h\coloneqq f_{x_{1}}a\cdot h_{1}+\cdots+f_{x_{k}}a\cdot h_{k}$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $f$ \end_inset v \begin_inset Formula $a$ \end_inset odvedljiva \begin_inset Formula $\Rightarrow f$ \end_inset v \begin_inset Formula $a$ \end_inset zvezna \end_layout \begin_layout Standard \begin_inset Formula $\forall i\in\left\{ 1..k\right\} :\exists f_{x_{i}}\wedge f_{x_{i}}$ \end_inset zvezna \begin_inset Formula $\Rightarrow f$ \end_inset odvedljiva \end_layout \begin_layout Standard Lagrange: \begin_inset Formula $fx_{1}-fx_{2}=f'\xi\left(x_{2}-x_{1}\right)$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $f\in C^{r}U\sim$ \end_inset \begin_inset Formula $f$ \end_inset \begin_inset Formula $r-$ \end_inset krat zvezno odvedljiva v vsaki točki \begin_inset Formula $U$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $f:U\subseteq\mathbb{R}^{k}\to\mathbb{R},f\in C^{2}U\Rightarrow\forall i,j\in\left\{ 1..k\right\} :f_{x_{i}}=f_{x_{j}}$ \end_inset \end_layout \begin_layout Standard \begin_inset Formula $\frac{df}{d\vec{s}}\left(x,y\right)=\lim_{t\to0}\frac{f((x,y)+t\vec{s})-f(x,y)}{t}=s_{1}f(x,y)+s_{2}f_{x}(x,y)$ \end_inset \end_layout \begin_layout Standard Tangentna ravnina v \begin_inset Formula $\left(x_{0},y_{0},f\left(x_{0},y_{0}\right)\right)$ \end_inset je \begin_inset Formula $f_{x}\left(x_{0},y_{0}\right)\left(x-x_{0}\right)+f_{y}\left(x_{0},y_{0}\right)\left(y-y_{0}\right)-z+f\left(x_{0},y_{0}\right)$ \end_inset in razpenjata jo vektorja \begin_inset Formula $\left(1,0,f_{x}\right)$ \end_inset in \begin_inset Formula $\left(0,1,f_{y}\right)$ \end_inset . \end_layout \begin_layout Section Taylorjeva formula in verižno pravilo \end_layout \begin_layout Standard \begin_inset Formula $f$ \end_inset diferenciabilna v \begin_inset Formula $a\in\mathbb{R}^{k}\Rightarrow f\left(a+h\right)\cong fa+dfa\cdot h=fa+f_{x_{1}}a\cdot h_{1}+\cdots+f_{x_{k}}a\cdot h_{k}$ \end_inset . \end_layout \begin_layout Standard \begin_inset Formula $U\subseteq R^{k}$ \end_inset odprta in \begin_inset Formula $f:U\to\mathbb{R},f\in C^{n+1}U$ \end_inset . Naj bo \begin_inset Formula $D_{f,r,a}$ \end_inset vektor vseh parcialnih odvodov reda \begin_inset Formula $r$ \end_inset v točki \begin_inset Formula $a$ \end_inset . Primer: \begin_inset Formula $D_{f,2,a}=\left(f_{xx}a,2f_{xy}a+f_{yy}a\right)$ \end_inset . \begin_inset Formula $D_{f,0,a}\coloneqq f\left(a\right)$ \end_inset . Naj bo \begin_inset Formula $H_{r}$ \end_inset vektor z vsemi kombinacijami dolžine \begin_inset Formula $r$ \end_inset komponent \begin_inset Formula $h$ \end_inset . Primer: \begin_inset Formula $H_{2}=\left(uu,2uv,vv\right)$ \end_inset . \begin_inset Formula $H_{0}=1$ \end_inset . \begin_inset Formula $D_{f,r,a}\cdot H_{r}$ \end_inset je njun skalarni produkt. \end_layout \begin_layout Standard \begin_inset Formula \[ T_{f,a,n}\left(h_{1}=x-a,h_{2}=y-b\right)=\sum_{i=0}^{n}\frac{1}{i!}\left(D_{f,i,a}\cdot H_{i}\right) \] \end_inset \end_layout \begin_layout Section Ekstremalni problemi \end_layout \begin_layout Standard Kandidati so \begin_inset Formula $a$ \end_inset , da \begin_inset Formula $\nabla fa=0$ \end_inset ali \begin_inset Formula $f$ \end_inset ni odv. v \begin_inset Formula $a$ \end_inset ali \begin_inset Formula $a$ \end_inset robna točka. \end_layout \begin_layout Standard \begin_inset Formula \[ H\left(a,b\right)=\left[\begin{array}{cc} f_{xx}\left(a,b\right) & f_{xy}\left(a,b\right)\\ f_{yx}\left(a,b\right) & f_{yy}\left(a,b\right) \end{array}\right] \] \end_inset \end_layout \begin_layout Standard \begin_inset Formula $\det H\left(a,b\right)>0$ \end_inset : \begin_inset Formula $f_{xx}\left(a,b\right)>0$ \end_inset l. min., \begin_inset Formula $f_{xx}\left(a,b\right)<0$ \end_inset l. max. \end_layout \begin_layout Standard \begin_inset Formula $\det H\left(a,b\right)<0$ \end_inset sedlo \end_layout \begin_layout Standard Izrek o implicitni funkciji: \begin_inset Formula $D\subseteq\mathbb{R}^{2}$ \end_inset odprta, \begin_inset Formula $f:D\to\mathbb{R}$ \end_inset zvezno parcialno odvedljiva. \begin_inset Formula $K=\left\{ \left(x,y\right)\in D;f\left(x,y\right)=0\right\} $ \end_inset . Za \begin_inset Formula $\left(a,b\right)\in D$ \end_inset , \begin_inset Formula $f\left(a,b\right)=0\wedge\nabla f\left(a,b\right)\not=0\exists h\left(a\right)=b,f\left(x,h\left(x\right)\right)=0\forall x\in U$ \end_inset . \end_layout \begin_layout Standard Vezani ekstrem: \begin_inset Formula $D^{\text{odp.}}\subseteq\mathbb{R}^{n}$ \end_inset , \begin_inset Formula $f:D\to\mathbb{R}$ \end_inset diferenciabilna na \begin_inset Formula $D$ \end_inset . let \begin_inset Formula $g:D\to\mathbb{R}$ \end_inset zvezno parcialno odvedljiva, \begin_inset Formula $A\coloneqq\left\{ x\in D;gx=0\right\} $ \end_inset . \begin_inset Formula $\exists$ \end_inset vezani ekstrem \begin_inset Formula $f$ \end_inset pri pogoju \begin_inset Formula $g\Leftrightarrow\nabla fa=\lambda\nabla ga$ \end_inset . Kandidati za vezane ekstreme so stac. točke fje \begin_inset Formula $F\left(x,\lambda\right)=fx-\lambda gx$ \end_inset . \end_layout \begin_layout Section Krivulje in ploskve \end_layout \begin_layout Standard Pot v \begin_inset Formula $\mathbb{R}^{3}\sim\vec{r}:I\to\mathbb{R}^{3},I\in\mathbb{R}$ \end_inset interval. \begin_inset Formula $\forall t\in I:\vec{r}t=\left(xt,yt,zt\right)$ \end_inset . \end_layout \begin_layout Standard Odvod poti: \begin_inset Formula $\dot{\vec{r}}\left(t\right)=\left(\dot{x}\left(t\right),\dot{y}\left(t\right),\dot{z}\left(t\right)\right)$ \end_inset . \begin_inset Formula $\dot{\vec{r}}t$ \end_inset je tangentni vektor na krivuljo v točki \begin_inset Formula $\vec{r}t$ \end_inset . \end_layout \begin_layout Standard Dolžina poti \begin_inset Formula $\vec{r}:\left[a,b\right]\to\mathbb{R}^{3}$ \end_inset je \begin_inset Formula \[ L=\int_{a}^{b}\left|\dot{\vec{r}}t\right|dt=\int_{a}^{b}\sqrt{\dot{x}^{2}t+\dot{y}^{2}t}dt \] \end_inset . \end_layout \begin_layout Standard Ploščina območja, ki ga omejuje krivulja, če je parametrizacija taka, da je krivulja levo od \begin_inset Formula $\vec{r}t$ \end_inset : \begin_inset Formula $\text{Pl\left(D\right)=\ensuremath{\frac{1}{2}\int_{a}^{b}\left(xt\dot{y}t-\dot{x}tyt\right)dt}}$ \end_inset . \end_layout \begin_layout Standard Ploskev eksplicitno kot graf \begin_inset Formula $f:D^{\text{odp.}}\subseteq\mathbb{R}^{2}\to\mathbb{R}$ \end_inset . \begin_inset Formula $f$ \end_inset difer. v \begin_inset Formula $\left(x,y\right)\Rightarrow$ \end_inset v \begin_inset Formula $\left(x,y,f\left(x,y\right)\right)$ \end_inset definiramo tangentno ravnino z normalo \begin_inset Formula $\left(-f_{x}\left(x,y\right),-f_{y}\left(x,y\right),1\right)$ \end_inset \end_layout \begin_layout Standard Ploskev implicitno: \begin_inset Formula $f:\mathbb{R}^{3}\to\mathbb{R}$ \end_inset zvezno parcialno odvedljiva. \begin_inset Formula \[ P=\left\{ \left(x,y,z\right)\in\mathbb{R}^{3};f\left(x,y,z\right)=0\right\} \] \end_inset Če \begin_inset Formula $\forall\left(x,y,z\right)\in P:\nabla f\left(x,y,z\right)\not=0\Rightarrow P$ \end_inset ploskev v \begin_inset Formula $\mathbb{R}^{3}$ \end_inset , saj je po izreku o implicitni fji \begin_inset Formula $P$ \end_inset lokalno graf fje dveh spremenljivk. Normala tangentne ravnine v \begin_inset Formula $\left(x,y,z\right)\in P$ \end_inset ima normalo \begin_inset Formula $\nabla f\left(x,y,z\right)$ \end_inset . \end_layout \begin_layout Standard \begin_inset ERT status open \begin_layout Plain Layout \backslash end{multicols} \end_layout \end_inset \end_layout \end_body \end_document