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 derivative(−2sin(2x)−cos(x))sign(−sin(x)+cos(2x))=0Solve this equationThe roots of this equation
x1=23.5619449019235x2=−58.1194640914112x3=−78.2871360846027x4=−6.53586556232167x5=−17.2787595947439x6=45.553093477052x7=56.2959875094742x8=36.1283155162826x9=−102.101761241668x10=73.8274273593601x11=−51.8362787842316x12=−25.3854214838604x13=−53.1543948558844x14=−67.5442420521806x15=−9.1720977056273x16=1.5707963267949x17=87.7119140453721x18=−72.0039507774232x19=−117.809724509617x20=−83.2522053201295x21=66.2261259805277x22=−64.4026493985908x23=−75.6509039412971x24=97.6420525164257x25=−45.553093477052x26=6.03050505203751x27=48.6946861306418x28=−65.7207654702436x29=34.8101994446298x30=64.4026493985908x31=−81.9340892484767x32=58.1194640914112x33=43.729616895115x34=80.1106126665397x35=−28.0216536271661x36=51.8362787842316x37=−15.4552830128069x38=86.3937979737193x39=−59.437580163064x40=28.5270141374502x41=−80.1106126665397x42=−50.5181627125788x43=−88.2172745556563x44=22.2438288302706x45=37.4464315879354x46=14.1371669411541x47=−21.7384683199865x48=95.8185759344887x49=100.278284659731x50=92.6769832808989x51=−44.2349774053992x52=53.6597553661686x53=−86.3937979737193x54=7.85398163397448x55=50.0128022022946x56=−20.4203522483337x57=59.9429406733481x58=−0.252680255142079x59=−89.5353906273091x60=−95.8185759344887x61=−36.1283155162826x62=89.5353906273091x63=−42.4115008234622x64=−14.1371669411541x65=67.5442420521806x66=−31.66860679104x67=−34.3048389343456x68=−103.419877313321x69=−23.5619449019235x70=9.67745821591146x71=93.9950993525517x72=−73.8274273593601x73=81.4287287381925x74=12.3136903592171x75=29.845130209103x76=18.5968756663967x77=62.5791728166538x78=78.7924965948869x79=−94.5004598628359x80=−1.5707963267949x81=42.4115008234622x82=−97.1366920061415x83=20.4203522483337x84=−29.845130209103x85=−37.9517920982196x86=−61.261056745001x87=26.7035375555132x88=−70.6858347057703x89=−7.85398163397448x90=70.6858347057703x91=15.960643523091x92=72.5093112877073The values of the extrema at the points:
(23.5619449019235, 0)
(-58.1194640914112, 0)
(-78.2871360846027, 1.125)
(-6.53586556232167, 1.125)
(-17.2787595947439, 2)
(45.553093477052, 2)
(56.2959875094742, 1.125)
(36.1283155162826, 0)
(-102.101761241668, 0)
(73.8274273593601, 0)
(-51.8362787842316, 0)
(-25.3854214838604, 1.125)
(-53.1543948558844, 1.125)
(-67.5442420521806, 2)
(-9.1720977056273, 1.125)
(1.5707963267949, 2)
(87.7119140453721, 1.125)
(-72.0039507774232, 1.125)
(-117.809724509617, 2)
(-83.2522053201295, 0)
(66.2261259805277, 1.125)
(-64.4026493985908, 0)
(-75.6509039412971, 1.125)
(97.6420525164257, 1.125)
(-45.553093477052, 0)
(6.03050505203751, 1.125)
(48.6946861306418, 0)
(-65.7207654702436, 1.125)
(34.8101994446298, 1.125)
(64.4026493985908, 2)
(-81.9340892484767, 1.125)
(58.1194640914112, 2)
(43.729616895115, 1.125)
(80.1106126665397, 0)
(-28.0216536271661, 1.125)
(51.8362787842316, 2)
(-15.4552830128069, 1.125)
(86.3937979737193, 0)
(-59.437580163064, 1.125)
(28.5270141374502, 1.125)
(-80.1106126665397, 2)
(-50.5181627125788, 1.125)
(-88.2172745556563, 1.125)
(22.2438288302706, 1.125)
(37.4464315879354, 1.125)
(14.1371669411541, 2)
(-21.7384683199865, 1.125)
(95.8185759344887, 2)
(100.278284659731, 1.125)
(92.6769832808989, 0)
(-44.2349774053992, 1.125)
(53.6597553661686, 1.125)
(-86.3937979737193, 2)
(7.85398163397448, 2)
(50.0128022022946, 1.125)
(-20.4203522483337, 0)
(59.9429406733481, 1.125)
(-0.252680255142079, 1.125)
(-89.5353906273091, 0)
(-95.8185759344887, 0)
(-36.1283155162826, 2)
(89.5353906273091, 2)
(-42.4115008234622, 2)
(-14.1371669411541, 0)
(67.5442420521806, 0)
(-31.66860679104, 1.125)
(-34.3048389343456, 1.125)
(-103.419877313321, 1.125)
(-23.5619449019235, 2)
(9.67745821591146, 1.125)
(93.9950993525517, 1.125)
(-73.8274273593601, 2)
(81.4287287381925, 1.125)
(12.3136903592171, 1.125)
(29.845130209103, 0)
(18.5968756663967, 1.125)
(62.5791728166538, 1.125)
(78.7924965948869, 1.125)
(-94.5004598628359, 1.125)
(-1.5707963267949, 0)
(42.4115008234622, 0)
(-97.1366920061415, 1.125)
(20.4203522483337, 2)
(-29.845130209103, 2)
(-37.9517920982196, 1.125)
(-61.261056745001, 2)
(26.7035375555132, 2)
(-70.6858347057703, 0)
(-7.85398163397448, 0)
(70.6858347057703, 2)
(15.960643523091, 1.125)
(72.5093112877073, 1.125)
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=23.5619449019235x2=−58.1194640914112x3=36.1283155162826x4=−102.101761241668x5=73.8274273593601x6=−51.8362787842316x7=−83.2522053201295x8=−64.4026493985908x9=−45.553093477052x10=48.6946861306418x11=80.1106126665397x12=86.3937979737193x13=92.6769832808989x14=−20.4203522483337x15=−89.5353906273091x16=−95.8185759344887x17=−14.1371669411541x18=67.5442420521806x19=29.845130209103x20=−1.5707963267949x21=42.4115008234622x22=−70.6858347057703x23=−7.85398163397448Maxima of the function at points:
x23=−78.2871360846027x23=−6.53586556232167x23=−17.2787595947439x23=45.553093477052x23=56.2959875094742x23=−25.3854214838604x23=−53.1543948558844x23=−67.5442420521806x23=−9.1720977056273x23=1.5707963267949x23=87.7119140453721x23=−72.0039507774232x23=−117.809724509617x23=66.2261259805277x23=−75.6509039412971x23=97.6420525164257x23=6.03050505203751x23=−65.7207654702436x23=34.8101994446298x23=64.4026493985908x23=−81.9340892484767x23=58.1194640914112x23=43.729616895115x23=−28.0216536271661x23=51.8362787842316x23=−15.4552830128069x23=−59.437580163064x23=28.5270141374502x23=−80.1106126665397x23=−50.5181627125788x23=−88.2172745556563x23=22.2438288302706x23=37.4464315879354x23=14.1371669411541x23=−21.7384683199865x23=95.8185759344887x23=100.278284659731x23=−44.2349774053992x23=53.6597553661686x23=−86.3937979737193x23=7.85398163397448x23=50.0128022022946x23=59.9429406733481x23=−0.252680255142079x23=−36.1283155162826x23=89.5353906273091x23=−42.4115008234622x23=−31.66860679104x23=−34.3048389343456x23=−103.419877313321x23=−23.5619449019235x23=9.67745821591146x23=93.9950993525517x23=−73.8274273593601x23=81.4287287381925x23=12.3136903592171x23=18.5968756663967x23=62.5791728166538x23=78.7924965948869x23=−94.5004598628359x23=−97.1366920061415x23=20.4203522483337x23=−29.845130209103x23=−37.9517920982196x23=−61.261056745001x23=26.7035375555132x23=70.6858347057703x23=15.960643523091x23=72.5093112877073Decreasing at intervals
[92.6769832808989,∞)Increasing at intervals
(−∞,−102.101761241668]