In order to find the extrema, we need to solve the equation
dxdf(x)=0(the derivative equals zero),
and the roots of this equation are the extrema of this function:
dxdf(x)=the first derivativex2(x+π)cos(2x)+sin(2x)−x2(x+π)sin(2x)=0Solve this equationThe roots of this equation
x1=85.6082964375406x2=76.1834918869339x3=−40.0558374988357x4=−27.4901091027858x5=46.3381490906586x6=11.7765020277599x7=−11.7886765310287x8=88.7498961593776x9=33.7714909991948x10=−76.1837629907443x11=−82.4669272166792x12=74.6126901432743x13=−18.0670702786868x14=−84.0377190116962x15=−60.4758850946187x16=8.63165183105941x17=1379.94457267781x18=−16.4969261458718x19=−62.0466697996072x20=69.9002827130884x21=24.3461694681355x22=−24.3488640507118x23=−99.7456482595368x24=−5.55606806484886x25=−4.11405638825337x26=60.4754544373262x27=18.0621070333104x28=−41.626592921105x29=−10.2210285897057x30=2.29351925513312x31=98.1746914639647x32=−98.1748546056604x33=−32.2021639665302x34=−2.05016185736717x35=−63.6174553767823x36=−77.754553554868x37=66.7586755813446x38=90.3206957514585x39=−91.8916814216247x40=80.8958953011203x41=52.6214092890184x42=10.204409368318x43=19.6331976071127x44=63.617066304661x45=−19.6373786282684x46=54.1922204947954x47=−57.3343187030552x48=−47.9096541504974x49=−35.3436074269189x50=25.9170965300131x51=32.200634568733x52=−46.3388840031421x53=−49.4804268340229x54=3.89840458387666x55=−79.3253444648916x56=99.7454902207637x57=27.488002883706x58=96.6038925895545x59=91.8914951802279x60=49.4797826464554x61=−55.7635372545373x62=55.7630304932234x63=16.4909355757335x64=47.9089668434327x65=38.4840197213942x66=62.0462607270261x67=−132.732335274511x68=84.0374962811429x69=82.4666959078989x70=41.6256811889882x71=−38.4850874210213x72=40.0548524056392x73=−85.6085110585658x74=−165.71904162811x75=68.3294793913564x76=−54.1927571597434x77=−93.4624744831675x78=−90.3208885350595x79=77.7542933118256x80=−69.9006048481523x81=−13.3575240618592x82=44.7673291188129x83=−68.3298165391845x84=−25.9194696918391x85=−33.772880226083x86=−71.4713936919086x87=30.6297691007327The values of the extrema at the points:
(85.60829643754059, 0.999999978628136 + 0.0116811105960709*pi)
(76.18349188693392, 0.999999966219436 + 0.0131262028223065*pi)
(-40.05583749883565, 0.999999435726337 - 0.0249651361241768*pi)
(-27.490109102785798, 0.999997246341827 - 0.0363766197726909*pi)
(46.33814909065861, -0.999999765319291 - 0.0215804857324541*pi)
(11.776502027759934, -0.999960030899051 - 0.084911464248205*pi)
(-11.788676531028724, 0.999881296649131 - 0.0848170949484758*pi)
(88.74989615937758, 0.999999981450874 + 0.0112676186083088*pi)
(33.7714909991948, -0.999999206132327 - 0.0296107508595392*pi)
(-76.18376299074434, -0.999999960158328 + 0.0131261560324845*pi)
(-82.46692721667922, -0.999999971171218 + 0.012126072898821*pi)
(74.61269014327426, -0.999999963344791 - 0.0134025453501884*pi)
(-18.06707027868685, 0.999983034496115 - 0.0553483779645095*pi)
(-84.03771901169623, 0.999999973306484 - 0.0118994183215195*pi)
(-60.475885094618725, -0.99999989738371 + 0.0165355148720707*pi)
(8.631651831059406, -0.999880559451095 - 0.115838842787102*pi)
(1379.944572677808, 0.999999999999661 + 0.000724666787202288*pi)
(-16.496926145871825, -0.999974585728353 + 0.0606158127208799*pi)
(-62.04666979960715, 0.999999907643538 - 0.016116898954823*pi)
(69.90028271308837, 0.999999952673103 + 0.0143060931066286*pi)
(24.346169468135457, -0.999997245340557 - 0.0410741101038241*pi)
(-24.348864050711843, 0.999995373210449 - 0.0410694877234412*pi)
(-99.7456482595368, 0.999999986712872 - 0.0100254999006161*pi)
(-5.556068064848859, 0.993214356555512 - 0.178762093077873*pi)
(-4.114056388253371, -0.930825509268131 + 0.226254922495925*pi)
(60.47545443732618, 0.999999916650229 + 0.0165356329432229*pi)
(18.062107033310397, -0.999991589067126 - 0.0553640606393776*pi)
(-41.62659292110495, -0.999999519288263 + 0.0240230931506589*pi)
(-10.221028589705744, -0.999764457230767 + 0.0978144663676701*pi)
(2.2935192551331154, -0.992153911526171 - 0.432590181794043*pi)
(98.17469146396473, 0.999999987530411 + 0.0101859244232763*pi)
(-98.17485460566041, -0.999999985827125 + 0.0101859074795051*pi)
(-32.20216396653017, -0.999998591261348 + 0.0310537699361047*pi)
(-2.0501618573671747, 0.818463147168178 - 0.399218795446352*pi)
(-63.61745537678228, -0.999999916652424 + 0.0157189549743824*pi)
(-77.75455355486802, 0.999999963345312 - 0.0128609826386522*pi)
(66.75867558134459, 0.999999943345213 + 0.014979325677705*pi)
(90.32069575145854, -0.999999982687397 - 0.0110716594283016*pi)
(-91.89168142162467, -0.999999981451032 + 0.0108823776644455*pi)
(80.8958953011203, -0.999999973306185 - 0.0123615663017742*pi)
(52.621409289018374, -0.99999985671774 - 0.0190036692332836*pi)
(10.204409368317986, 0.999933489791241 + 0.0979903347366455*pi)
(19.63319760711271, 0.999993829577657 + 0.0509338239032128*pi)
(63.617066304661, 0.999999931601397 + 0.0157190513440594*pi)
(-19.637378628268372, -0.999988243202298 + 0.0509226950364341*pi)
(54.1922204947954, 0.999999872204922 + 0.01845283073981*pi)
(-57.33431870305522, -0.99999987220956 + 0.0174415584737082*pi)
(-47.90965415049744, -0.999999731819662 + 0.0208726142893536*pi)
(-35.34360742691894, -0.999999047595807 + 0.0282936327216608*pi)
(25.917096530013072, 0.999997824878058 + 0.0385844850992479*pi)
(32.200634568732966, 0.999999047439765 + 0.0310552590292979*pi)
(-46.33888400314214, 0.999999692103051 - 0.0215801418962796*pi)
(-49.48042683402295, 0.999999765332728 - 0.02021000685154*pi)
(3.8984045838766574, 0.998366099685432 + 0.256096071663407*pi)
(-79.3253444648916, -0.999999966219888 + 0.0126063110468115*pi)
(99.74549022076374, -0.9999999882861 - 0.0100255158009934*pi)
(27.488002883705988, -0.999998259637466 - 0.0363794439293454*pi)
(96.60389258955452, -0.999999986712784 - 0.0103515496105476*pi)
(91.89149518022786, 0.999999983822574 + 0.0108823997461491*pi)
(49.47978264645545, -0.999999818017476 - 0.0202102710345902*pi)
(-55.763537254537255, 0.999999856723406 - 0.0179328626905217*pi)
(55.763030493223404, -0.999999885654735 - 0.017933026178989*pi)
(16.490935575733467, 0.999988230472177 + 0.060638659697614*pi)
(47.90896684343273, 0.999999793759002 + 0.0208729150229229*pi)
(38.48401972139424, 0.999999519241118 + 0.0259847990537535*pi)
(62.04626072702611, -0.99999992458719 - 0.0161170054870303*pi)
(-132.7323352745114, -0.999999995830266 + 0.00753395918004538*pi)
(84.03749628114294, -0.999999977015298 - 0.011899449903527*pi)
(82.46669590789888, 0.999999975247394 + 0.0121261069603689*pi)
(41.625681188988175, 0.999999644724284 + 0.0240236223446796*pi)
(-38.48508742102131, -0.999999333184957 + 0.0259840733176752*pi)
(40.054852405639195, -0.999999587899441 - 0.0249657539059775*pi)
(-85.60851105856578, -0.999999975247656 + 0.0116810812719724*pi)
(-165.71904162811032, 0.999999998300409 - 0.00603430956681796*pi)
(68.32947939135637, -0.99999994827114 - 0.0146349709843924*pi)
(-54.19275715974343, -0.999999838818255 + 0.0184526473873726*pi)
(-93.46247448316745, 0.999999982687537 - 0.0106994811363317*pi)
(-90.32088853505948, 0.999999980102128 - 0.011071635767998*pi)
(77.75429331182563, -0.999999968817703 - 0.0128610257546462*pi)
(-69.90060484815228, -0.99999994334633 + 0.0143060270439529*pi)
(-13.357524061859186, -0.99993375414123 + 0.0748592141410713*pi)
(44.76732911881294, 0.999999731802688 + 0.0223377126017207*pi)
(-68.32981653918449, 0.999999937819972 - 0.0146348986206704*pi)
(-25.919469691839065, -0.99999646060738 + 0.038580899705762*pi)
(-33.772880226082954, 0.999998847230964 - 0.0296095222124011*pi)
(-71.47139369190862, 0.999999948272093 - 0.013991611141414*pi)
(30.62976910073273, -0.999998847012987 - 0.0326479394514621*pi)
Intervals of increase and decrease of the function:Let's find intervals where the function increases and decreases, as well as minima and maxima of the function, for this let's look how the function behaves itself in the extremas and at the slightest deviation from:
Minima of the function at points:
x1=46.3381490906586x2=11.7765020277599x3=33.7714909991948x4=−76.1837629907443x5=−82.4669272166792x6=74.6126901432743x7=−60.4758850946187x8=8.63165183105941x9=−16.4969261458718x10=24.3461694681355x11=−4.11405638825337x12=18.0621070333104x13=−41.626592921105x14=−10.2210285897057x15=2.29351925513312x16=−98.1748546056604x17=−32.2021639665302x18=−2.05016185736717x19=−63.6174553767823x20=90.3206957514585x21=−91.8916814216247x22=80.8958953011203x23=52.6214092890184x24=−19.6373786282684x25=−57.3343187030552x26=−47.9096541504974x27=−35.3436074269189x28=−79.3253444648916x29=99.7454902207637x30=27.488002883706x31=96.6038925895545x32=49.4797826464554x33=55.7630304932234x34=62.0462607270261x35=−132.732335274511x36=84.0374962811429x37=−38.4850874210213x38=40.0548524056392x39=−85.6085110585658x40=68.3294793913564x41=−54.1927571597434x42=77.7542933118256x43=−69.9006048481523x44=−13.3575240618592x45=−25.9194696918391x46=30.6297691007327Maxima of the function at points:
x46=85.6082964375406x46=76.1834918869339x46=−40.0558374988357x46=−27.4901091027858x46=−11.7886765310287x46=88.7498961593776x46=−18.0670702786868x46=−84.0377190116962x46=1379.94457267781x46=−62.0466697996072x46=69.9002827130884x46=−24.3488640507118x46=−99.7456482595368x46=−5.55606806484886x46=60.4754544373262x46=98.1746914639647x46=−77.754553554868x46=66.7586755813446x46=10.204409368318x46=19.6331976071127x46=63.617066304661x46=54.1922204947954x46=25.9170965300131x46=32.200634568733x46=−46.3388840031421x46=−49.4804268340229x46=3.89840458387666x46=91.8914951802279x46=−55.7635372545373x46=16.4909355757335x46=47.9089668434327x46=38.4840197213942x46=82.4666959078989x46=41.6256811889882x46=−165.71904162811x46=−93.4624744831675x46=−90.3208885350595x46=44.7673291188129x46=−68.3298165391845x46=−33.772880226083x46=−71.4713936919086Decreasing at intervals
[99.7454902207637,∞)Increasing at intervals
(−∞,−132.732335274511]