Sr Examen

Gráfico de la función y = sin(x)/sqrt(12+x)

v

Gráfico:

interior superior

Puntos de intersección:

mostrar?

Definida a trozos:

Solución

Ha introducido [src]
         sin(x)  
f(x) = ----------
         ________
       \/ 12 + x 
$$f{\left(x \right)} = \frac{\sin{\left(x \right)}}{\sqrt{x + 12}}$$
f = sin(x)/sqrt(x + 12)
Gráfico de la función
Dominio de definición de la función
Puntos en los que la función no está definida exactamente:
$$x_{1} = -12$$
Puntos de cruce con el eje de coordenadas X
El gráfico de la función cruce el eje X con f = 0
o sea hay que resolver la ecuación:
$$\frac{\sin{\left(x \right)}}{\sqrt{x + 12}} = 0$$
Resolvermos esta ecuación
Puntos de cruce con el eje X:

Solución analítica
$$x_{1} = 0$$
$$x_{2} = \pi$$
Solución numérica
$$x_{1} = 59.6902604182061$$
$$x_{2} = -100.530964914873$$
$$x_{3} = -116.238928182822$$
$$x_{4} = -15.707963267949$$
$$x_{5} = -25.1327412287183$$
$$x_{6} = 84.8230016469244$$
$$x_{7} = 0$$
$$x_{8} = 317.300858012569$$
$$x_{9} = -75.398223686155$$
$$x_{10} = -50.2654824574367$$
$$x_{11} = 97.3893722612836$$
$$x_{12} = 81.6814089933346$$
$$x_{13} = -72.2566310325652$$
$$x_{14} = 125.663706143592$$
$$x_{15} = 91.106186954104$$
$$x_{16} = 50.2654824574367$$
$$x_{17} = -43.9822971502571$$
$$x_{18} = -37.6991118430775$$
$$x_{19} = 113.097335529233$$
$$x_{20} = 25.1327412287183$$
$$x_{21} = -65.9734457253857$$
$$x_{22} = -53.4070751110265$$
$$x_{23} = -18.8495559215388$$
$$x_{24} = -59.6902604182061$$
$$x_{25} = 15.707963267949$$
$$x_{26} = 9.42477796076938$$
$$x_{27} = 18.8495559215388$$
$$x_{28} = 273.318560862312$$
$$x_{29} = 131.946891450771$$
$$x_{30} = -56.5486677646163$$
$$x_{31} = -6.28318530717959$$
$$x_{32} = -62.8318530717959$$
$$x_{33} = 12.5663706143592$$
$$x_{34} = 56.5486677646163$$
$$x_{35} = 40.8407044966673$$
$$x_{36} = 3.14159265358979$$
$$x_{37} = -21.9911485751286$$
$$x_{38} = -84.8230016469244$$
$$x_{39} = 6.28318530717959$$
$$x_{40} = 69.1150383789755$$
$$x_{41} = 72.2566310325652$$
$$x_{42} = -78.5398163397448$$
$$x_{43} = 37.6991118430775$$
$$x_{44} = 21.9911485751286$$
$$x_{45} = 47.1238898038469$$
$$x_{46} = 34.5575191894877$$
$$x_{47} = -97.3893722612836$$
$$x_{48} = -31.4159265358979$$
$$x_{49} = 100.530964914873$$
$$x_{50} = -47.1238898038469$$
$$x_{51} = 28.2743338823081$$
$$x_{52} = 94.2477796076938$$
$$x_{53} = -40.8407044966673$$
$$x_{54} = -34.5575191894877$$
$$x_{55} = -28.2743338823081$$
$$x_{56} = 78.5398163397448$$
$$x_{57} = -94.2477796076938$$
$$x_{58} = -91.106186954104$$
$$x_{59} = 144.51326206513$$
$$x_{60} = 43.9822971502571$$
$$x_{61} = 75.398223686155$$
$$x_{62} = 62.8318530717959$$
$$x_{63} = 345.575191894877$$
$$x_{64} = -3.14159265358979$$
$$x_{65} = 87.9645943005142$$
$$x_{66} = 53.4070751110265$$
$$x_{67} = -81.6814089933346$$
$$x_{68} = -87.9645943005142$$
$$x_{69} = 65.9734457253857$$
$$x_{70} = -69.1150383789755$$
$$x_{71} = 31.4159265358979$$
$$x_{72} = -9.42477796076938$$
Puntos de cruce con el eje de coordenadas Y
El gráfico cruce el eje Y cuando x es igual a 0:
sustituimos x = 0 en sin(x)/sqrt(12 + x).
$$\frac{\sin{\left(0 \right)}}{\sqrt{12}}$$
Resultado:
$$f{\left(0 \right)} = 0$$
Punto:
(0, 0)
Extremos de la función
Para hallar los extremos hay que resolver la ecuación
$$\frac{d}{d x} f{\left(x \right)} = 0$$
(la derivada es igual a cero),
y las raíces de esta ecuación serán los extremos de esta función:
$$\frac{d}{d x} f{\left(x \right)} = $$
primera derivada
$$\frac{\cos{\left(x \right)}}{\sqrt{x + 12}} - \frac{\sin{\left(x \right)}}{2 \left(x + 12\right)^{\frac{3}{2}}} = 0$$
Resolvermos esta ecuación
Raíces de esta ecuación
$$x_{1} = -83.2451874174528$$
$$x_{2} = -20.3606192102297$$
$$x_{3} = 80.1051841437789$$
$$x_{4} = 95.8139383484481$$
$$x_{5} = -246.612892139843$$
$$x_{6} = -61.2509049960415$$
$$x_{7} = -92.6707853296145$$
$$x_{8} = 20.4049237186924$$
$$x_{9} = -58.1086205572355$$
$$x_{10} = -17.1825802243184$$
$$x_{11} = -23.518563946472$$
$$x_{12} = 83.2469558567458$$
$$x_{13} = -64.3931064480803$$
$$x_{14} = 45.544404753626$$
$$x_{15} = 86.388716133896$$
$$x_{16} = 67.537955828092$$
$$x_{17} = 98.9556623140844$$
$$x_{18} = 2159.84471912395$$
$$x_{19} = 64.3961046557234$$
$$x_{20} = 10.9738138135803$$
$$x_{21} = -42.3950522612964$$
$$x_{22} = 17.2616740600802$$
$$x_{23} = -4.78154542352293$$
$$x_{24} = -32.9628756948497$$
$$x_{25} = -13.8768038497918$$
$$x_{26} = 89.530466036912$$
$$x_{27} = -26.6694663426443$$
$$x_{28} = -89.5289415121996$$
$$x_{29} = -39.2515626565503$$
$$x_{30} = -95.8126103158704$$
$$x_{31} = 51.8284454464525$$
$$x_{32} = 32.975606183108$$
$$x_{33} = 7.82877109194837$$
$$x_{34} = 130.372583226299$$
$$x_{35} = 58.1123327993243$$
$$x_{36} = 36.11792475218$$
$$x_{37} = -54.9662349182927$$
$$x_{38} = -76.9613232773934$$
$$x_{39} = 70.6797873522282$$
$$x_{40} = 48.6864472451997$$
$$x_{41} = -7.97765278370313$$
$$x_{42} = -98.9544185123724$$
$$x_{43} = 739.844404889277$$
$$x_{44} = -73.8193394518863$$
$$x_{45} = -45.5381862021436$$
$$x_{46} = -67.5352390029499$$
$$x_{47} = -86.3870764772726$$
$$x_{48} = 23.5478802931037$$
$$x_{49} = -48.6810559604372$$
$$x_{50} = -51.8237241138463$$
$$x_{51} = 54.970405592188$$
$$x_{52} = 29.8331785427431$$
$$x_{53} = 39.2601543142646$$
$$x_{54} = -174.355312618809$$
$$x_{55} = 4.68242629059323$$
$$x_{56} = 73.8216013862378$$
$$x_{57} = -1.6189236967475$$
$$x_{58} = -70.6773137311895$$
$$x_{59} = 26.6906152443659$$
$$x_{60} = -80.1032710071855$$
$$x_{61} = 92.6722064999962$$
$$x_{62} = -29.8170746041252$$
$$x_{63} = 61.2542313067072$$
$$x_{64} = 1.53386877017751$$
$$x_{65} = 42.4023102960826$$
$$x_{66} = 14.1180254124872$$
$$x_{67} = 76.9633997833194$$
$$x_{68} = -36.1075781231631$$
Signos de extremos en los puntos:
(-83.24518741745281, 0.118470859314563*I)

(-20.36061921022968, 0.345227614913729*I)

(80.10518414377891, -0.104196123854939)

(95.81393834844815, 0.0963070043817124)

(-246.61289213984344, 0.0652864534545343*I)

(-61.25090499604148, -0.142485448341385*I)

(-92.67078532961446, -0.111335462075447*I)

(20.404923718692416, 0.175647837207681)

(-58.10862055723546, 0.147259527305094*I)

(-17.18258022431841, -0.437235246704616*I)

(-23.51856394647204, -0.29436898605305*I)

(83.2469558567458, 0.102463329489896)

(-64.39310644808029, 0.13814753816133*I)

(45.54440475362601, 0.131820227093036)

(86.38871613389604, -0.10081420863209)

(67.53795582809201, -0.112125451909898)

(98.95566231408445, -0.0949337978787364)

(2159.8447191239497, -0.0214578202487205)

(64.39610465572345, 0.114407656900476)

(10.973813813580266, -0.208583821586473)

(-42.39505226129637, -0.181359287035697*I)

(17.261674060080185, -0.18483619686771)

(-4.781545423522932, 0.371311607475296)

(-32.96287569484965, 0.218348930912355*I)

(-13.876803849791798, 0.70534403100327*I)

(89.53046603691197, 0.0992422367551707)

(-26.66946634264428, 0.260940036537687*I)

(-89.52894151219957, 0.113568801119825*I)

(-39.25156265655028, 0.191527530038943*I)

(-95.81261031587036, 0.109228907168797*I)

(51.82844544645252, 0.125164031103941)

(32.975606183108034, 0.149102405997137)

(7.828771091948365, 0.224498825462677)

(130.37258322629853, -0.0838077419113687)

(58.11233279932431, 0.119424037054501)

(36.11792475218, -0.14415280923776)

(-54.96623491829275, -0.152548150435439*I)

(-76.96132327739336, 0.12406797807474*I)

(70.67978735222825, 0.109974598037377)

(48.68644724519966, -0.128362865458639)

(-7.977652783703126, -0.494800979651768)

(-98.95441851237238, -0.107237577018031*I)

(739.8444048892768, -0.036470012981631)

(-73.81933945188635, -0.127181404055952*I)

(-45.53818620214362, 0.172656111825905*I)

(-67.53523900294994, -0.134183178859072*I)

(-86.38707647727259, -0.115942175274977*I)

(23.547880293103667, -0.16770661356137)

(-48.681055960437156, -0.165096832866985*I)

(-51.823724113846254, 0.158450946253176*I)

(54.97040559218799, -0.122193029354218)

(29.8331785427431, -0.154599665307182)

(39.26015431426459, 0.13966557900936)

(-174.3553126188085, -0.0784810289540689*I)

(4.682426290593226, -0.244723354365609)

(73.82160138623779, -0.107942959874844)

(-1.6189236967474974, -0.310009960783476)

(-70.67731373118954, 0.130541657196597*I)

(26.690615244365915, 0.16075367884391)

(-80.10327100718554, -0.121172567414615*I)

(92.67220649999618, -0.0977415800959035)

(-29.81707460412521, -0.23681590008574*I)

(61.254231306707204, -0.116835151500422)

(1.5338687701775138, 0.271639448781314)

(42.40231029608263, -0.135572931404926)

(14.118025412487205, 0.195636670366637)

(76.96339978331943, 0.106019915869813)

(-36.1075781231631, -0.203624401120097*I)


Intervalos de crecimiento y decrecimiento de la función:
Hallemos los intervalos donde la función crece y decrece y también los puntos mínimos y máximos de la función, para lo cual miramos cómo se comporta la función en los extremos con desviación mínima del extremo:
Puntos mínimos de la función:
$$x_{1} = 80.1051841437789$$
$$x_{2} = 86.388716133896$$
$$x_{3} = 67.537955828092$$
$$x_{4} = 98.9556623140844$$
$$x_{5} = 2159.84471912395$$
$$x_{6} = 10.9738138135803$$
$$x_{7} = 17.2616740600802$$
$$x_{8} = 130.372583226299$$
$$x_{9} = 36.11792475218$$
$$x_{10} = 48.6864472451997$$
$$x_{11} = -7.97765278370313$$
$$x_{12} = 739.844404889277$$
$$x_{13} = 23.5478802931037$$
$$x_{14} = 54.970405592188$$
$$x_{15} = 29.8331785427431$$
$$x_{16} = 4.68242629059323$$
$$x_{17} = 73.8216013862378$$
$$x_{18} = -1.6189236967475$$
$$x_{19} = 92.6722064999962$$
$$x_{20} = 61.2542313067072$$
$$x_{21} = 42.4023102960826$$
Puntos máximos de la función:
$$x_{21} = 95.8139383484481$$
$$x_{21} = 20.4049237186924$$
$$x_{21} = 83.2469558567458$$
$$x_{21} = 45.544404753626$$
$$x_{21} = 64.3961046557234$$
$$x_{21} = -4.78154542352293$$
$$x_{21} = 89.530466036912$$
$$x_{21} = 51.8284454464525$$
$$x_{21} = 32.975606183108$$
$$x_{21} = 7.82877109194837$$
$$x_{21} = 58.1123327993243$$
$$x_{21} = 70.6797873522282$$
$$x_{21} = 39.2601543142646$$
$$x_{21} = 26.6906152443659$$
$$x_{21} = 1.53386877017751$$
$$x_{21} = 14.1180254124872$$
$$x_{21} = 76.9633997833194$$
Decrece en los intervalos
$$\left[2159.84471912395, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -7.97765278370313\right]$$
Puntos de flexiones
Hallemos los puntos de flexiones, para eso hay que resolver la ecuación
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = 0$$
(la segunda derivada es igual a cero),
las raíces de la ecuación obtenida serán los puntos de flexión para el gráfico de la función indicado:
$$\frac{d^{2}}{d x^{2}} f{\left(x \right)} = $$
segunda derivada
$$\frac{- \sin{\left(x \right)} - \frac{\cos{\left(x \right)}}{x + 12} + \frac{3 \sin{\left(x \right)}}{4 \left(x + 12\right)^{2}}}{\sqrt{x + 12}} = 0$$
Resolvermos esta ecuación
Soluciones no halladas,
tal vez la función no tenga flexiones
Asíntotas verticales
Hay:
$$x_{1} = -12$$
Asíntotas horizontales
Hallemos las asíntotas horizontales mediante los límites de esta función con x->+oo y x->-oo
$$\lim_{x \to -\infty}\left(\frac{\sin{\left(x \right)}}{\sqrt{x + 12}}\right) = 0$$
Tomamos como el límite
es decir,
ecuación de la asíntota horizontal a la izquierda:
$$y = 0$$
$$\lim_{x \to \infty}\left(\frac{\sin{\left(x \right)}}{\sqrt{x + 12}}\right) = 0$$
Tomamos como el límite
es decir,
ecuación de la asíntota horizontal a la derecha:
$$y = 0$$
Asíntotas inclinadas
Se puede hallar la asíntota inclinada calculando el límite de la función sin(x)/sqrt(12 + x), dividida por x con x->+oo y x ->-oo
$$\lim_{x \to -\infty}\left(\frac{\sin{\left(x \right)}}{x \sqrt{x + 12}}\right) = 0$$
Tomamos como el límite
es decir,
la inclinada coincide con la asíntota horizontal a la derecha
$$\lim_{x \to \infty}\left(\frac{\sin{\left(x \right)}}{x \sqrt{x + 12}}\right) = 0$$
Tomamos como el límite
es decir,
la inclinada coincide con la asíntota horizontal a la izquierda
Paridad e imparidad de la función
Comprobemos si la función es par o impar mediante las relaciones f = f(-x) и f = -f(-x).
Pues, comprobamos:
$$\frac{\sin{\left(x \right)}}{\sqrt{x + 12}} = - \frac{\sin{\left(x \right)}}{\sqrt{12 - x}}$$
- No
$$\frac{\sin{\left(x \right)}}{\sqrt{x + 12}} = \frac{\sin{\left(x \right)}}{\sqrt{12 - x}}$$
- No
es decir, función
no es
par ni impar