Sr Examen

Gráfico de la función y = |π-x|*sin2x

v

Gráfico:

interior superior

Puntos de intersección:

mostrar?

Definida a trozos:

Solución

Ha introducido [src]
f(x) = |pi - x|*sin(2*x)
$$f{\left(x \right)} = \sin{\left(2 x \right)} \left|{\pi - x}\right|$$
f = sin(2*x)*|pi - x|
Gráfico de la función
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:
$$\sin{\left(2 x \right)} \left|{\pi - x}\right| = 0$$
Resolvermos esta ecuación
Puntos de cruce con el eje X:

Solución analítica
$$x_{1} = 0$$
$$x_{2} = \frac{\pi}{2}$$
$$x_{3} = \pi$$
Solución numérica
$$x_{1} = 65.9734457253857$$
$$x_{2} = 23.5619449019235$$
$$x_{3} = -86.3937979737193$$
$$x_{4} = 100.530964914873$$
$$x_{5} = 3.14159304793669$$
$$x_{6} = -95.8185759344887$$
$$x_{7} = -6.28318530717959$$
$$x_{8} = 72.2566310325652$$
$$x_{9} = -83.2522053201295$$
$$x_{10} = -75.398223686155$$
$$x_{11} = -50.2654824574367$$
$$x_{12} = 95.8185759344887$$
$$x_{13} = -59.6902604182061$$
$$x_{14} = -53.4070751110265$$
$$x_{15} = 45.553093477052$$
$$x_{16} = 56.5486677646163$$
$$x_{17} = 20.4203522483337$$
$$x_{18} = -80.1106126665397$$
$$x_{19} = -15.707963267949$$
$$x_{20} = 37.6991118430775$$
$$x_{21} = -14.1371669411541$$
$$x_{22} = -29.845130209103$$
$$x_{23} = -94.2477796076938$$
$$x_{24} = 78.5398163397448$$
$$x_{25} = 70.6858347057703$$
$$x_{26} = 81.6814089933346$$
$$x_{27} = -72.2566310325652$$
$$x_{28} = 50.2654824574367$$
$$x_{29} = -21.9911485751286$$
$$x_{30} = 3.14159261471774$$
$$x_{31} = 15.707963267949$$
$$x_{32} = -37.6991118430775$$
$$x_{33} = 48.6946861306418$$
$$x_{34} = -97.3893722612836$$
$$x_{35} = 21.9911485751286$$
$$x_{36} = -20.4203522483337$$
$$x_{37} = -61.261056745001$$
$$x_{38} = 26.7035375555132$$
$$x_{39} = -51.8362787842316$$
$$x_{40} = 6.28318530717959$$
$$x_{41} = 3.14159278900492$$
$$x_{42} = -28.2743338823081$$
$$x_{43} = 43.9822971502571$$
$$x_{44} = -81.6814089933346$$
$$x_{45} = -42.4115008234622$$
$$x_{46} = -17.2787595947439$$
$$x_{47} = 51.8362787842316$$
$$x_{48} = -65.9734457253857$$
$$x_{49} = 73.8274273593601$$
$$x_{50} = 29.845130209103$$
$$x_{51} = -58.1194640914112$$
$$x_{52} = 42.4115008234622$$
$$x_{53} = 59.6902604182061$$
$$x_{54} = -31.4159265358979$$
$$x_{55} = -9.42477796076938$$
$$x_{56} = -23.5619449019235$$
$$x_{57} = -64.4026493985908$$
$$x_{58} = -89.5353906273091$$
$$x_{59} = -73.8274273593601$$
$$x_{60} = 64.4026493985908$$
$$x_{61} = 17.2787595947439$$
$$x_{62} = 80.1106126665397$$
$$x_{63} = -39.2699081698724$$
$$x_{64} = 36.1283155162826$$
$$x_{65} = 0$$
$$x_{66} = -45.553093477052$$
$$x_{67} = 14.1371669411541$$
$$x_{68} = 3.14159337572662$$
$$x_{69} = 92.6769832808989$$
$$x_{70} = 67.5442420521806$$
$$x_{71} = 28.2743338823081$$
$$x_{72} = 12.5663706143592$$
$$x_{73} = 94.2477796076938$$
$$x_{74} = 58.1194640914112$$
$$x_{75} = -7.85398163397448$$
$$x_{76} = 7.85398163397448$$
$$x_{77} = 3.14159263757671$$
$$x_{78} = -87.9645943005142$$
$$x_{79} = -67.5442420521806$$
$$x_{80} = -43.9822971502571$$
$$x_{81} = 89.5353906273091$$
$$x_{82} = 86.3937979737193$$
$$x_{83} = -36.1283155162826$$
$$x_{84} = -1.5707963267949$$
$$x_{85} = -62.8318530717959$$
$$x_{86} = 4.71238898038469$$
$$x_{87} = 34.5575191894877$$
$$x_{88} = 87.9645943005142$$
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 |pi - x|*sin(2*x).
$$\sin{\left(0 \cdot 2 \right)} \left|{\pi - 0}\right|$$
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
$$- \sin{\left(2 x \right)} \operatorname{sign}{\left(\pi - x \right)} + 2 \cos{\left(2 x \right)} \left|{\pi - x}\right| = 0$$
Resolvermos esta ecuación
Raíces de esta ecuación
$$x_{1} = 41.6325973187992$$
$$x_{2} = -84.0404710143993$$
$$x_{3} = 90.3236563215789$$
$$x_{4} = -77.757508406196$$
$$x_{5} = -76.1867732656521$$
$$x_{6} = 96.6066488688146$$
$$x_{7} = 69.9041810845183$$
$$x_{8} = 77.7577686061303$$
$$x_{9} = 68.3334749736689$$
$$x_{10} = 32.2099242760394$$
$$x_{11} = 66.7627733168536$$
$$x_{12} = -93.464969237122$$
$$x_{13} = -19.6459232442052$$
$$x_{14} = 62.0506986325689$$
$$x_{15} = 33.7802799203746$$
$$x_{16} = 49.4854785395983$$
$$x_{17} = 55.7680199232732$$
$$x_{18} = 22.7892681443263$$
$$x_{19} = 40.0620772281003$$
$$x_{20} = 8.6843618568383$$
$$x_{21} = 82.4699585728317$$
$$x_{22} = -24.3564336251584$$
$$x_{23} = -68.3331378981873$$
$$x_{24} = 11.8097816155815$$
$$x_{25} = -47.9141844162372$$
$$x_{26} = -46.3435434906081$$
$$x_{27} = -40.0610927522545$$
$$x_{28} = 98.1774009878104$$
$$x_{29} = 30.639618932338$$
$$x_{30} = 88.752912605287$$
$$x_{31} = -54.1968332417517$$
$$x_{32} = 76.1870443226817$$
$$x_{33} = 0.685002433872351$$
$$x_{34} = -62.0502896664894$$
$$x_{35} = -49.4848346160936$$
$$x_{36} = 4.15597157264501$$
$$x_{37} = -33.7788919209207$$
$$x_{38} = 25.9291085513848$$
$$x_{39} = -13.3669078630888$$
$$x_{40} = 47.9148714227144$$
$$x_{41} = 63.6213847531168$$
$$x_{42} = -27.497094613195$$
$$x_{43} = 84.0406937133755$$
$$x_{44} = -91.8942156806308$$
$$x_{45} = 91.8944018999488$$
$$x_{46} = -90.3234635616351$$
$$x_{47} = -60.479588009674$$
$$x_{48} = 46.3442780594341$$
$$x_{49} = 5.59818287330723$$
$$x_{50} = -82.4697272981074$$
$$x_{51} = -22.7861877109862$$
$$x_{52} = 2.12721373453458$$
$$x_{53} = 52.6267287977876$$
$$x_{54} = 10.2453110161854$$
$$x_{55} = -71.4745832989507$$
$$x_{56} = -18.0759382871152$$
$$x_{57} = 71.4748913423179$$
$$x_{58} = -63.6209957773387$$
$$x_{59} = -55.7675133253893$$
$$x_{60} = -57.3381994459372$$
$$x_{61} = 54.1973697234168$$
$$x_{62} = 19.6500931702684$$
$$x_{63} = -79.3282458772952$$
$$x_{64} = -69.9038590155021$$
$$x_{65} = -99.7479965214271$$
$$x_{66} = 106.031181828607$$
$$x_{67} = 27.4991980123687$$
$$x_{68} = -35.3494120116196$$
$$x_{69} = -5.52659630840189$$
$$x_{70} = -11.7977005994639$$
$$x_{71} = -41.6316861155348$$
$$x_{72} = -10.2288653538039$$
$$x_{73} = 74.6163232053669$$
$$x_{74} = -85.6112165927692$$
$$x_{75} = 18.0808859066435$$
$$x_{76} = -32.2083963657152$$
$$x_{77} = -38.4905146984545$$
$$x_{78} = -2.40117654965872$$
$$x_{79} = 38.4915816728948$$
$$x_{80} = -16.5060828371467$$
$$x_{81} = -98.1772378630566$$
$$x_{82} = 16.5120506609834$$
$$x_{83} = 24.3591235942947$$
$$x_{84} = 99.7481545443016$$
$$x_{85} = 85.6114311844748$$
$$x_{86} = -3.9621257090058$$
$$x_{87} = -25.9267389688598$$
$$x_{88} = 60.4800185489313$$
Signos de extremos en los puntos:
(41.63259731879916, 41.6290851929716 - 0.999915640001976*pi)

(-84.04047101439932, 84.0390889334277 + 0.999983554578468*pi)

(90.32365632157891, -90.3221709109764 + 0.999983554578468*pi)

(-77.75750840619597, 77.7560233170795 + 0.999980901019761*pi)

(-76.18677326565214, -76.1852599844512 - 0.999980137218889*pi)

(96.60664886881464, -96.6052665469866 + 0.999985691235084*pi)

(69.90418108451833, 69.9022207573258 - 0.999971956939312*pi)

(77.75776860613026, -77.7560228917033 + 0.999977549324546*pi)

(68.33347497366894, -68.331465245507 + 0.999970589404933*pi)

(32.209924276039374, 32.205160370442 - 0.999852098205616*pi)

(66.76277331685361, 66.760711638952 - 0.999969119349015*pi)

(-93.464969237122, 93.4637174314859 + 0.99998660668648*pi)

(-19.645923244205218, -19.6411957423843 - 0.99975936474137*pi)

(62.05069863256893, -62.0484636797429 + 0.999963981826549*pi)

(33.780279920374625, -33.7757826788193 + 0.999866867842247*pi)

(49.48547853959829, -49.4825987219882 + 0.999941804794153*pi)

(55.768019923273194, -55.7655030690477 + 0.999954869220228*pi)

(22.789268144326286, 22.7818923778362 - 0.99967634912875*pi)

(40.06207722810025, -40.0584039910265 + 0.99990831136756*pi)

(8.684361856838304, -8.64924192674639 + 0.995955957309142*pi)

(82.46995857283171, 82.4683204900964 - 0.999980137218889*pi)

(-24.356433625158402, 24.3524081885715 + 0.999834727996355*pi)

(-68.33313789818735, 68.331465959357 + 0.999975532532505*pi)

(11.809781615581473, -11.7901835575469 + 0.998340523248224*pi)

(-47.91418441623717, -47.9118869290689 - 0.999952049957727*pi)

(-46.343543490608056, 46.3411780259716 + 0.999948958054169*pi)

(-40.06109275225448, 40.0584100795286 + 0.999933035458057*pi)

(98.17740098781042, 98.1760422427377 - 0.999986160307168*pi)

(30.63961893233799, -30.6345550611261 + 0.999834727996355*pi)

(88.75291260528697, 88.7513989773633 - 0.999982945597172*pi)

(-54.196833241751705, -54.1947727654469 - 0.999961981610704*pi)

(76.18704432268167, 76.1852595228368 - 0.999976573446828*pi)

(0.6850024338723514, -0.67124007206977 + 0.979909032257328*pi)

(-62.05028966648936, 62.0484647305462 + 0.999970589404933*pi)

(-49.48483461609361, 49.4826013269205 + 0.999954869220228*pi)

(4.155971572645011, 3.72772205177638 - 0.896955618347486*pi)

(-33.778891920920664, 33.7757947805151 + 0.99990831136756*pi)

(25.929108551384804, 25.9228690936425 - 0.99975936474137*pi)

(-13.366907863088828, -13.360781157028 - 0.999541651208824*pi)

(47.91487142271439, 47.9118839639231 - 0.999937650697945*pi)

(63.62138475311677, 63.6192106993024 - 0.999965828253773*pi)

(-27.497094613195035, 27.4934338656572 + 0.999866867842247*pi)

(84.04069371337555, -84.0390886218271 + 0.999980901019761*pi)

(-91.89421568063084, -91.8929438929127 - 0.999986160307168*pi)

(91.89440189994882, 91.8929436750343 - 0.999984131515257*pi)

(-90.32346356163507, 90.3221711444285 + 0.999985691235084*pi)

(-60.47958800967403, -60.477720360625 - 0.999969119349014*pi)

(46.34427805943407, -46.3411746360822 + 0.999933035458057*pi)

(5.598182873307235, -5.48570996178204 + 0.979909032257328*pi)

(-82.46972729810737, -82.4683208261569 - 0.999982945597172*pi)

(-22.78618771098619, -22.7819519651238 - 0.99981410905957*pi)

(2.127213734534576, 1.90801631061672 - 0.896955618347486*pi)

(52.62672879778764, -52.6240426271471 + 0.999948958054169*pi)

(10.245311016185388, 10.2200265566482 - 0.997532094487196*pi)

(-71.47458329895068, 71.4729786462778 + 0.999977549324546*pi)

(-18.07593828711515, 18.0709213305809 + 0.999722451114041*pi)

(71.47489134231787, -71.472978050096 + 0.999973231267849*pi)

(-63.620995777338734, -63.6192116498931 - 0.999971956939312*pi)

(-55.767513325389345, 55.7655046814215 + 0.999963981826549*pi)

(-57.338199445937185, -57.3362400995366 - 0.999965828253773*pi)

(54.197369723416756, 54.1947709572474 - 0.999952049957727*pi)

(19.650093170268416, 19.6410865738173 - 0.999541651208824*pi)

(-79.32824587729517, -79.3267879508854 - 0.999981621597785*pi)

(-69.90385901550209, -69.9022214090319 - 0.999976573446828*pi)

(-99.74799652142714, 99.746818742889 + 0.999988192459205*pi)

(106.03118182860673, -106.029929861102 + 0.999988192459205*pi)

(27.499198012368655, -27.4934060779343 + 0.999789378059981*pi)

(-35.34941201161957, -35.3464299352921 - 0.999915640001976*pi)

(-5.526596308401887, 5.51742505031164 + 0.998340523248224*pi)

(-11.797700599463903, 11.7910984917354 + 0.999440390297005*pi)

(-41.631686115534805, -41.6290904089621 - 0.999937650697945*pi)

(-10.228865353803862, -10.2217205601104 - 0.999301506721775*pi)

(74.61632320536694, -74.6144975329043 + 0.999975532532505*pi)

(-85.61121659276924, -85.6098580724849 - 0.999984131515257*pi)

(18.08088590664349, -18.0707676674514 + 0.999440390297005*pi)

(-32.20839636571521, -32.2051750344276 - 0.999899984735313*pi)

(-38.49051469845453, -38.4877390787403 - 0.999927888215163*pi)

(-2.401176549658718, 2.39146608918361 + 0.995955957309142*pi)

(38.491581672894796, 38.4877319271656 - 0.999899984735313*pi)

(-16.5060828371467, -16.5007406290555 - 0.99967634912875*pi)

(-98.17723786305656, -98.1760424099262 - 0.999987823520437*pi)

(16.512050660983448, 16.500517104587 - 0.999301506721775*pi)

(24.359123594294736, -24.3523627466782 + 0.999722451114041*pi)

(99.74815454430158, -99.7468185859947 + 0.99998660668648*pi)

(85.61143118447477, 85.6098577831582 - 0.999981621597785*pi)

(-3.962125709005801, -3.95234755712612 - 0.997532094487196*pi)

(-25.926738968859787, -25.9229043576438 - 0.999852098205616*pi)

(60.48001854893129, 60.4777191960414 - 0.999961981610704*pi)


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:
$$x_{1} = 90.3236563215789$$
$$x_{2} = -76.1867732656521$$
$$x_{3} = 96.6066488688146$$
$$x_{4} = 77.7577686061303$$
$$x_{5} = 68.3334749736689$$
$$x_{6} = -19.6459232442052$$
$$x_{7} = 62.0506986325689$$
$$x_{8} = 33.7802799203746$$
$$x_{9} = 49.4854785395983$$
$$x_{10} = 55.7680199232732$$
$$x_{11} = 40.0620772281003$$
$$x_{12} = 8.6843618568383$$
$$x_{13} = 11.8097816155815$$
$$x_{14} = -47.9141844162372$$
$$x_{15} = 30.639618932338$$
$$x_{16} = -54.1968332417517$$
$$x_{17} = -13.3669078630888$$
$$x_{18} = 84.0406937133755$$
$$x_{19} = -91.8942156806308$$
$$x_{20} = -60.479588009674$$
$$x_{21} = 46.3442780594341$$
$$x_{22} = 5.59818287330723$$
$$x_{23} = -82.4697272981074$$
$$x_{24} = -22.7861877109862$$
$$x_{25} = 2.12721373453458$$
$$x_{26} = 52.6267287977876$$
$$x_{27} = 71.4748913423179$$
$$x_{28} = -63.6209957773387$$
$$x_{29} = -57.3381994459372$$
$$x_{30} = -79.3282458772952$$
$$x_{31} = -69.9038590155021$$
$$x_{32} = 106.031181828607$$
$$x_{33} = 27.4991980123687$$
$$x_{34} = -35.3494120116196$$
$$x_{35} = -41.6316861155348$$
$$x_{36} = -10.2288653538039$$
$$x_{37} = 74.6163232053669$$
$$x_{38} = -85.6112165927692$$
$$x_{39} = 18.0808859066435$$
$$x_{40} = -32.2083963657152$$
$$x_{41} = -38.4905146984545$$
$$x_{42} = -16.5060828371467$$
$$x_{43} = -98.1772378630566$$
$$x_{44} = 24.3591235942947$$
$$x_{45} = 99.7481545443016$$
$$x_{46} = -3.9621257090058$$
$$x_{47} = -25.9267389688598$$
Puntos máximos de la función:
$$x_{47} = 41.6325973187992$$
$$x_{47} = -84.0404710143993$$
$$x_{47} = -77.757508406196$$
$$x_{47} = 69.9041810845183$$
$$x_{47} = 32.2099242760394$$
$$x_{47} = 66.7627733168536$$
$$x_{47} = -93.464969237122$$
$$x_{47} = 22.7892681443263$$
$$x_{47} = 82.4699585728317$$
$$x_{47} = -24.3564336251584$$
$$x_{47} = -68.3331378981873$$
$$x_{47} = -46.3435434906081$$
$$x_{47} = -40.0610927522545$$
$$x_{47} = 98.1774009878104$$
$$x_{47} = 88.752912605287$$
$$x_{47} = 76.1870443226817$$
$$x_{47} = 0.685002433872351$$
$$x_{47} = -62.0502896664894$$
$$x_{47} = -49.4848346160936$$
$$x_{47} = 4.15597157264501$$
$$x_{47} = -33.7788919209207$$
$$x_{47} = 25.9291085513848$$
$$x_{47} = 47.9148714227144$$
$$x_{47} = 63.6213847531168$$
$$x_{47} = -27.497094613195$$
$$x_{47} = 91.8944018999488$$
$$x_{47} = -90.3234635616351$$
$$x_{47} = 10.2453110161854$$
$$x_{47} = -71.4745832989507$$
$$x_{47} = -18.0759382871152$$
$$x_{47} = -55.7675133253893$$
$$x_{47} = 54.1973697234168$$
$$x_{47} = 19.6500931702684$$
$$x_{47} = -99.7479965214271$$
$$x_{47} = -5.52659630840189$$
$$x_{47} = -11.7977005994639$$
$$x_{47} = -2.40117654965872$$
$$x_{47} = 38.4915816728948$$
$$x_{47} = 16.5120506609834$$
$$x_{47} = 85.6114311844748$$
$$x_{47} = 60.4800185489313$$
Decrece en los intervalos
$$\left[106.031181828607, \infty\right)$$
Crece en los intervalos
$$\left(-\infty, -98.1772378630566\right]$$
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
$$2 \left(- 2 \sin{\left(2 x \right)} \left|{x - \pi}\right| + \sin{\left(2 x \right)} \delta\left(x - \pi\right) + 2 \cos{\left(2 x \right)} \operatorname{sign}{\left(x - \pi \right)}\right) = 0$$
Resolvermos esta ecuación
Soluciones no halladas,
tal vez la función no tenga flexiones
Asíntotas horizontales
Hallemos las asíntotas horizontales mediante los límites de esta función con x->+oo y x->-oo
$$\lim_{x \to -\infty}\left(\sin{\left(2 x \right)} \left|{\pi - x}\right|\right) = \left\langle -\infty, \infty\right\rangle$$
Tomamos como el límite
es decir,
ecuación de la asíntota horizontal a la izquierda:
$$y = \left\langle -\infty, \infty\right\rangle$$
$$\lim_{x \to \infty}\left(\sin{\left(2 x \right)} \left|{\pi - x}\right|\right) = \left\langle -\infty, \infty\right\rangle$$
Tomamos como el límite
es decir,
ecuación de la asíntota horizontal a la derecha:
$$y = \left\langle -\infty, \infty\right\rangle$$
Asíntotas inclinadas
Se puede hallar la asíntota inclinada calculando el límite de la función |pi - x|*sin(2*x), dividida por x con x->+oo y x ->-oo
$$\lim_{x \to -\infty}\left(\frac{\sin{\left(2 x \right)} \left|{\pi - x}\right|}{x}\right) = \left\langle -1, 1\right\rangle$$
Tomamos como el límite
es decir,
ecuación de la asíntota inclinada a la izquierda:
$$y = \left\langle -1, 1\right\rangle x$$
$$\lim_{x \to \infty}\left(\frac{\sin{\left(2 x \right)} \left|{\pi - x}\right|}{x}\right) = \left\langle -1, 1\right\rangle$$
Tomamos como el límite
es decir,
ecuación de la asíntota inclinada a la derecha:
$$y = \left\langle -1, 1\right\rangle x$$
Gráfico
Gráfico de la función y = |π-x|*sin2x