#title: Domínio de função #author: Smirnov #let: n a = [1,2,3,4]; n b = [-1,1,-2,2,-3,3,-4,4]; n c = [-1,1,-2,2,-3,3,-4,4]; f F1 = [sqrt(z), sqrt(-z), log(z), log(-z), 1/z, 1/sqrt(z), 1/sqrt(-z)]; s S = [\geq, \leq, >, <, \neq, >, <]; f D0 = [ #a^2-(x+#b)^2-(y+#c)^2]; f D1 = ratsimp(#D0); f d = ratsimp(-#b); f e = ratsimp(-#c); f aux1 = [F(z) := #F1]; f G = ratsimp(F(#D1)); fig1 = {{ \begin{tikzpicture}[scale=0.5] \fill[blue!20] (#d,#e) circle (#a); \draw[->](-8,0)--(8,0) node[right]{$x$}; \draw[->](0,-8)--(0,8) node[above]{$y$}; \node at (#d,#e) [below] {$(#d,#e)$}; \filldraw[black] (#d,#e) circle(1.5pt); \foreach \x/\xtext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6, } \draw[shift={(\x,0)}] (0pt,0.3pt) -- (0pt,-0.3pt) node[below] {$\xtext$}; \foreach \y/\ytext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6} \draw[shift={(0,\y)}] (0.3pt,0pt) -- (-0.3pt,0pt) node[left] {$\ytext$}; \foreach \x in {-7,...,7} \draw (\x cm,-1pt) -- (\x cm,1pt); \foreach \y in {-7,...,7} \draw (-1pt,\y cm) -- (1pt,\y cm); \end{tikzpicture} }}; fig2 = {{ \begin{tikzpicture}[scale=0.5] \filldraw[blue!20] (-7,-7) rectangle (7,7); \filldraw[white] (#d,#e) circle (#a); \draw[->](-8,0)--(8,0) node[right]{$x$}; \draw[->](0,-8)--(0,8) node[above]{$y$}; \node at (#d,#e) [below] {$(#d,#e)$}; \filldraw[black] (#d,#e) circle(1.5pt); \foreach \x/\xtext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6, } \draw[shift={(\x,0)}] (0pt,0.3pt) -- (0pt,-0.3pt) node[below] {$\xtext$}; \foreach \y/\ytext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6} \draw[shift={(0,\y)}] (0.3pt,0pt) -- (-0.3pt,0pt) node[left] {$\ytext$}; \foreach \x in {-7,...,7} \draw (\x cm,-1pt) -- (\x cm,1pt); \foreach \y in {-7,...,7} \draw (-1pt,\y cm) -- (1pt,\y cm); \end{tikzpicture} }}; fig3 = {{ \begin{tikzpicture}[scale=0.5] \draw[style=dashed,color=black] (#d,#e) circle (#a); \fill[blue!20] (#d,#e) circle (#a); \draw[->](-8,0)--(8,0) node[right]{$x$}; \draw[->](0,-8)--(0,8) node[above]{$y$}; \node at (#d,#e) [below] {$(#d,#e)$}; \filldraw[black] (#d,#e) circle(1.5pt); \foreach \x/\xtext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6, } \draw[shift={(\x,0)}] (0pt,0.3pt) -- (0pt,-0.3pt) node[below] {$\xtext$}; \foreach \y/\ytext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6} \draw[shift={(0,\y)}] (0.3pt,0pt) -- (-0.3pt,0pt) node[left] {$\ytext$}; \foreach \x in {-7,...,7} \draw (\x cm,-1pt) -- (\x cm,1pt); \foreach \y in {-7,...,7} \draw (-1pt,\y cm) -- (1pt,\y cm); \end{tikzpicture} }}; fig4 = {{ \begin{tikzpicture}[scale=0.5] \filldraw[blue!20] (-7,-7) rectangle (7,7); \filldraw[white] (#d,#e) circle (#a); \draw[style=dashed,color=black] (#d,#e) circle (#a); \draw[->](-8,0)--(8,0) node[right]{$x$}; \draw[->](0,-8)--(0,8) node[above]{$y$}; \node at (#d,#e) [below] {$(#d,#e)$}; \filldraw[black] (#d,#e) circle(1.5pt); \foreach \x/\xtext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6, } \draw[shift={(\x,0)}] (0pt,0.3pt) -- (0pt,-0.3pt) node[below] {$\xtext$}; \foreach \y/\ytext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6} \draw[shift={(0,\y)}] (0.3pt,0pt) -- (-0.3pt,0pt) node[left] {$\ytext$}; \foreach \x in {-7,...,7} \draw (\x cm,-1pt) -- (\x cm,1pt); \foreach \y in {-7,...,7} \draw (-1pt,\y cm) -- (1pt,\y cm); \end{tikzpicture} }}; fig5 = {{ \begin{tikzpicture}[scale=0.5] \filldraw[blue!20] (-7,-7) rectangle (7,7); \draw[style=dashed,color=white] (#d,#e) circle (#a); \draw[->](-8,0)--(8,0) node[right]{$x$}; \draw[->](0,-8)--(0,8) node[above]{$y$}; \node at (#d,#e) [below] {$(#d,#e)$}; \filldraw[black] (#d,#e) circle(1.5pt); \foreach \x/\xtext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6, } \draw[shift={(\x,0)}] (0pt,0.3pt) -- (0pt,-0.3pt) node[below] {$\xtext$}; \foreach \y/\ytext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6} \draw[shift={(0,\y)}] (0.3pt,0pt) -- (-0.3pt,0pt) node[left] {$\ytext$}; \foreach \x in {-7,...,7} \draw (\x cm,-1pt) -- (\x cm,1pt); \foreach \y in {-7,...,7} \draw (-1pt,\y cm) -- (1pt,\y cm); \end{tikzpicture} }}; fig6 = {{ \begin{tikzpicture}[scale=0.5] \draw[style=dashed,color=black] (#d,#e) circle (#a); \fill[blue!20] (#d,#e) circle (#a); \draw[->](-8,0)--(8,0) node[right]{$x$}; \draw[->](0,-8)--(0,8) node[above]{$y$}; \node at (#d,#e) [below] {$(#d,#e)$}; \filldraw[black] (#d,#e) circle(1.5pt); \foreach \x/\xtext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6, } \draw[shift={(\x,0)}] (0pt,0.3pt) -- (0pt,-0.3pt) node[below] {$\xtext$}; \foreach \y/\ytext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6} \draw[shift={(0,\y)}] (0.3pt,0pt) -- (-0.3pt,0pt) node[left] {$\ytext$}; \foreach \x in {-7,...,7} \draw (\x cm,-1pt) -- (\x cm,1pt); \foreach \y in {-7,...,7} \draw (-1pt,\y cm) -- (1pt,\y cm); \end{tikzpicture} }}; fig7 = {{ \begin{tikzpicture}[scale=0.5] \filldraw[blue!20] (-7,-7) rectangle (7,7); \filldraw[white] (#d,#e) circle (#a); \draw[style=dashed,color=black] (#d,#e) circle (#a); \draw[->](-8,0)--(8,0) node[right]{$x$}; \draw[->](0,-8)--(0,8) node[above]{$y$}; \node at (#d,#e) [below] {$(#d,#e)$}; \filldraw[black] (#d,#e) circle(1.5pt); \foreach \x/\xtext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6, } \draw[shift={(\x,0)}] (0pt,0.3pt) -- (0pt,-0.3pt) node[below] {$\xtext$}; \foreach \y/\ytext in {-6/6, -4/4, -2/2, 2/2, 4/4, 6/6} \draw[shift={(0,\y)}] (0.3pt,0pt) -- (-0.3pt,0pt) node[left] {$\ytext$}; \foreach \x in {-7,...,7} \draw (\x cm,-1pt) -- (\x cm,1pt); \foreach \y in {-7,...,7} \draw (-1pt,\y cm) -- (1pt,\y cm); \end{tikzpicture} }}; Gr = [#fig1, #fig2, #fig3, #fig4, #fig5, #fig6, #fig7]; F1~S~Gr; #question: \noindent Determine e represente geometricamente o domínio da função $f(x,y)=#G$. #sugestion: #resolution: #result: $$ {\rm dom} f = \{ (x,y) \mid #D0 #S 0\}. $$ $$ #Gr $$ A área azul representa o domínio da função. #Verification: #usepackage: \usepackage{tikz}