Abs(cos(x))>sin(x) (неравенство)

Учитель очень удивится увидев твоё верное решение 😼

В неравенстве неизвестная

    Укажите решение неравенства: Abs(cos(x))>sin(x) (множество решений неравенства)

    Решение

    Вы ввели [src]
    |cos(x)| > sin(x)
    cos(x)>sin(x)\left|{\cos{\left (x \right )}}\right| > \sin{\left (x \right )}
    Подробное решение
    Дано неравенство:
    cos(x)>sin(x)\left|{\cos{\left (x \right )}}\right| > \sin{\left (x \right )}
    Чтобы решить это нер-во - надо сначала решить соотвествующее ур-ние:
    cos(x)=sin(x)\left|{\cos{\left (x \right )}}\right| = \sin{\left (x \right )}
    Решаем:
    x1=80.8960108299x_{1} = -80.8960108299
    x2=19.6349540849x_{2} = 19.6349540849
    x3=3.92699081699x_{3} = -3.92699081699
    x4=21.2057504117x_{4} = 21.2057504117
    x5=82.4668071567x_{5} = 82.4668071567
    x6=0.785398163397x_{6} = 0.785398163397
    x7=73.042029196x_{7} = -73.042029196
    x8=96.6039740979x_{8} = 96.6039740979
    x9=32.2013246993x_{9} = 32.2013246993
    x10=51.0508806208x_{10} = 51.0508806208
    x11=25.9181393921x_{11} = 25.9181393921
    x12=5.49778714378x_{12} = -5.49778714378
    x13=77.7544181763x_{13} = 77.7544181763
    x14=57.334065928x_{14} = 57.334065928
    x15=43.1968989869x_{15} = -43.1968989869
    x16=33.7721210261x_{16} = 33.7721210261
    x17=76.1836218496x_{17} = 76.1836218496
    x18=107.599548385x_{18} = 107.599548385
    x19=29.0597320457x_{19} = -29.0597320457
    x20=46.3384916404x_{20} = 46.3384916404
    x21=99.7455667515x_{21} = -99.7455667515
    x22=60.4756585816x_{22} = -60.4756585816
    x23=16.4933614313x_{23} = -16.4933614313
    x24=85.6083998103x_{24} = -85.6083998103
    x25=47.9092879672x_{25} = -47.9092879672
    x26=71.4712328692x_{26} = 71.4712328692
    x27=74.6128255228x_{27} = -74.6128255228
    x28=88.7499924639x_{28} = 88.7499924639
    x29=10.2101761242x_{29} = -10.2101761242
    x30=162.577419823x_{30} = -162.577419823
    x31=55.7632696012x_{31} = -55.7632696012
    x32=54.1924732744x_{32} = -54.1924732744
    x33=7.06858347058x_{33} = 7.06858347058
    x34=14.9225651046x_{34} = 14.9225651046
    x35=95.0331777711x_{35} = 95.0331777711
    x36=98.1747704247x_{36} = -98.1747704247
    x37=795.608339522x_{37} = -795.608339522
    x38=40.0553063333x_{38} = 40.0553063333
    x39=18.0641577581x_{39} = -18.0641577581
    x40=65.188047562x_{40} = 65.188047562
    x41=36.9137136797x_{41} = -36.9137136797
    x42=69.9004365424x_{42} = 69.9004365424
    x43=204.988920647x_{43} = -204.988920647
    x44=102.887159405x_{44} = 102.887159405
    x45=13.3517687778x_{45} = 13.3517687778
    x46=22.7765467385x_{46} = -22.7765467385
    x47=30.6305283725x_{47} = -30.6305283725
    x48=63.6172512352x_{48} = 63.6172512352
    x49=66.7588438888x_{49} = -66.7588438888
    x50=90.3207887907x_{50} = 90.3207887907
    x51=38.4845100065x_{51} = 38.4845100065
    x52=79.3252145031x_{52} = -79.3252145031
    x53=58.9048622548x_{53} = 58.9048622548
    x54=62.0464549084x_{54} = -62.0464549084
    x55=49.480084294x_{55} = -49.480084294
    x56=3667.0240249x_{56} = -3667.0240249
    x57=52.6216769476x_{57} = 52.6216769476
    x58=68.3296402156x_{58} = -68.3296402156
    x59=93.4623814443x_{59} = -93.4623814443
    x60=35.3429173529x_{60} = -35.3429173529
    x61=44.7676953137x_{61} = 44.7676953137
    x62=41.6261026601x_{62} = -41.6261026601
    x63=84.0376034835x_{63} = 84.0376034835
    x64=87.1791961371x_{64} = -87.1791961371
    x65=24.3473430653x_{65} = -24.3473430653
    x66=11.780972451x_{66} = -11.780972451
    x67=27.4889357189x_{67} = 27.4889357189
    x68=2.35619449019x_{68} = 2.35619449019
    x69=8.63937979737x_{69} = 8.63937979737
    x70=91.8915851175x_{70} = -91.8915851175
    x1=80.8960108299x_{1} = -80.8960108299
    x2=19.6349540849x_{2} = 19.6349540849
    x3=3.92699081699x_{3} = -3.92699081699
    x4=21.2057504117x_{4} = 21.2057504117
    x5=82.4668071567x_{5} = 82.4668071567
    x6=0.785398163397x_{6} = 0.785398163397
    x7=73.042029196x_{7} = -73.042029196
    x8=96.6039740979x_{8} = 96.6039740979
    x9=32.2013246993x_{9} = 32.2013246993
    x10=51.0508806208x_{10} = 51.0508806208
    x11=25.9181393921x_{11} = 25.9181393921
    x12=5.49778714378x_{12} = -5.49778714378
    x13=77.7544181763x_{13} = 77.7544181763
    x14=57.334065928x_{14} = 57.334065928
    x15=43.1968989869x_{15} = -43.1968989869
    x16=33.7721210261x_{16} = 33.7721210261
    x17=76.1836218496x_{17} = 76.1836218496
    x18=107.599548385x_{18} = 107.599548385
    x19=29.0597320457x_{19} = -29.0597320457
    x20=46.3384916404x_{20} = 46.3384916404
    x21=99.7455667515x_{21} = -99.7455667515
    x22=60.4756585816x_{22} = -60.4756585816
    x23=16.4933614313x_{23} = -16.4933614313
    x24=85.6083998103x_{24} = -85.6083998103
    x25=47.9092879672x_{25} = -47.9092879672
    x26=71.4712328692x_{26} = 71.4712328692
    x27=74.6128255228x_{27} = -74.6128255228
    x28=88.7499924639x_{28} = 88.7499924639
    x29=10.2101761242x_{29} = -10.2101761242
    x30=162.577419823x_{30} = -162.577419823
    x31=55.7632696012x_{31} = -55.7632696012
    x32=54.1924732744x_{32} = -54.1924732744
    x33=7.06858347058x_{33} = 7.06858347058
    x34=14.9225651046x_{34} = 14.9225651046
    x35=95.0331777711x_{35} = 95.0331777711
    x36=98.1747704247x_{36} = -98.1747704247
    x37=795.608339522x_{37} = -795.608339522
    x38=40.0553063333x_{38} = 40.0553063333
    x39=18.0641577581x_{39} = -18.0641577581
    x40=65.188047562x_{40} = 65.188047562
    x41=36.9137136797x_{41} = -36.9137136797
    x42=69.9004365424x_{42} = 69.9004365424
    x43=204.988920647x_{43} = -204.988920647
    x44=102.887159405x_{44} = 102.887159405
    x45=13.3517687778x_{45} = 13.3517687778
    x46=22.7765467385x_{46} = -22.7765467385
    x47=30.6305283725x_{47} = -30.6305283725
    x48=63.6172512352x_{48} = 63.6172512352
    x49=66.7588438888x_{49} = -66.7588438888
    x50=90.3207887907x_{50} = 90.3207887907
    x51=38.4845100065x_{51} = 38.4845100065
    x52=79.3252145031x_{52} = -79.3252145031
    x53=58.9048622548x_{53} = 58.9048622548
    x54=62.0464549084x_{54} = -62.0464549084
    x55=49.480084294x_{55} = -49.480084294
    x56=3667.0240249x_{56} = -3667.0240249
    x57=52.6216769476x_{57} = 52.6216769476
    x58=68.3296402156x_{58} = -68.3296402156
    x59=93.4623814443x_{59} = -93.4623814443
    x60=35.3429173529x_{60} = -35.3429173529
    x61=44.7676953137x_{61} = 44.7676953137
    x62=41.6261026601x_{62} = -41.6261026601
    x63=84.0376034835x_{63} = 84.0376034835
    x64=87.1791961371x_{64} = -87.1791961371
    x65=24.3473430653x_{65} = -24.3473430653
    x66=11.780972451x_{66} = -11.780972451
    x67=27.4889357189x_{67} = 27.4889357189
    x68=2.35619449019x_{68} = 2.35619449019
    x69=8.63937979737x_{69} = 8.63937979737
    x70=91.8915851175x_{70} = -91.8915851175
    Данные корни
    x56=3667.0240249x_{56} = -3667.0240249
    x37=795.608339522x_{37} = -795.608339522
    x43=204.988920647x_{43} = -204.988920647
    x30=162.577419823x_{30} = -162.577419823
    x21=99.7455667515x_{21} = -99.7455667515
    x36=98.1747704247x_{36} = -98.1747704247
    x59=93.4623814443x_{59} = -93.4623814443
    x70=91.8915851175x_{70} = -91.8915851175
    x64=87.1791961371x_{64} = -87.1791961371
    x24=85.6083998103x_{24} = -85.6083998103
    x1=80.8960108299x_{1} = -80.8960108299
    x52=79.3252145031x_{52} = -79.3252145031
    x27=74.6128255228x_{27} = -74.6128255228
    x7=73.042029196x_{7} = -73.042029196
    x58=68.3296402156x_{58} = -68.3296402156
    x49=66.7588438888x_{49} = -66.7588438888
    x54=62.0464549084x_{54} = -62.0464549084
    x22=60.4756585816x_{22} = -60.4756585816
    x31=55.7632696012x_{31} = -55.7632696012
    x32=54.1924732744x_{32} = -54.1924732744
    x55=49.480084294x_{55} = -49.480084294
    x25=47.9092879672x_{25} = -47.9092879672
    x15=43.1968989869x_{15} = -43.1968989869
    x62=41.6261026601x_{62} = -41.6261026601
    x41=36.9137136797x_{41} = -36.9137136797
    x60=35.3429173529x_{60} = -35.3429173529
    x47=30.6305283725x_{47} = -30.6305283725
    x19=29.0597320457x_{19} = -29.0597320457
    x65=24.3473430653x_{65} = -24.3473430653
    x46=22.7765467385x_{46} = -22.7765467385
    x39=18.0641577581x_{39} = -18.0641577581
    x23=16.4933614313x_{23} = -16.4933614313
    x66=11.780972451x_{66} = -11.780972451
    x29=10.2101761242x_{29} = -10.2101761242
    x12=5.49778714378x_{12} = -5.49778714378
    x3=3.92699081699x_{3} = -3.92699081699
    x6=0.785398163397x_{6} = 0.785398163397
    x68=2.35619449019x_{68} = 2.35619449019
    x33=7.06858347058x_{33} = 7.06858347058
    x69=8.63937979737x_{69} = 8.63937979737
    x45=13.3517687778x_{45} = 13.3517687778
    x34=14.9225651046x_{34} = 14.9225651046
    x2=19.6349540849x_{2} = 19.6349540849
    x4=21.2057504117x_{4} = 21.2057504117
    x11=25.9181393921x_{11} = 25.9181393921
    x67=27.4889357189x_{67} = 27.4889357189
    x9=32.2013246993x_{9} = 32.2013246993
    x16=33.7721210261x_{16} = 33.7721210261
    x51=38.4845100065x_{51} = 38.4845100065
    x38=40.0553063333x_{38} = 40.0553063333
    x61=44.7676953137x_{61} = 44.7676953137
    x20=46.3384916404x_{20} = 46.3384916404
    x10=51.0508806208x_{10} = 51.0508806208
    x57=52.6216769476x_{57} = 52.6216769476
    x14=57.334065928x_{14} = 57.334065928
    x53=58.9048622548x_{53} = 58.9048622548
    x48=63.6172512352x_{48} = 63.6172512352
    x40=65.188047562x_{40} = 65.188047562
    x42=69.9004365424x_{42} = 69.9004365424
    x26=71.4712328692x_{26} = 71.4712328692
    x17=76.1836218496x_{17} = 76.1836218496
    x13=77.7544181763x_{13} = 77.7544181763
    x5=82.4668071567x_{5} = 82.4668071567
    x63=84.0376034835x_{63} = 84.0376034835
    x28=88.7499924639x_{28} = 88.7499924639
    x50=90.3207887907x_{50} = 90.3207887907
    x35=95.0331777711x_{35} = 95.0331777711
    x8=96.6039740979x_{8} = 96.6039740979
    x44=102.887159405x_{44} = 102.887159405
    x18=107.599548385x_{18} = 107.599548385
    являются точками смены знака неравенства в решениях.
    Сначала определимся со знаком до крайней левой точки:
    x0<x56x_{0} < x_{56}
    Возьмём например точку
    x0=x56110x_{0} = x_{56} - \frac{1}{10}
    =
    3667.1240249-3667.1240249
    =
    3667.1240249-3667.1240249
    подставляем в выражение
    cos(x)>sin(x)\left|{\cos{\left (x \right )}}\right| > \sin{\left (x \right )}
    cos(3667.1240249)>sin(3667.1240249)\left|{\cos{\left (-3667.1240249 \right )}}\right| > \sin{\left (-3667.1240249 \right )}
    0.632981308756673 > 0.774167076776512

    Тогда
    x<3667.0240249x < -3667.0240249
    не выполняется
    значит одно из решений нашего неравенства будет при:
    x>3667.0240249x<795.608339522x > -3667.0240249 \wedge x < -795.608339522
             _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____           _____  
            /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \         /     \  
    -------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------ο-------
           x56      x37      x43      x30      x21      x36      x59      x70      x64      x24      x1      x52      x27      x7      x58      x49      x54      x22      x31      x32      x55      x25      x15      x62      x41      x60      x47      x19      x65      x46      x39      x23      x66      x29      x12      x3      x6      x68      x33      x69      x45      x34      x2      x4      x11      x67      x9      x16      x51      x38      x61      x20      x10      x57      x14      x53      x48      x40      x42      x26      x17      x13      x5      x63      x28      x50      x35      x8      x44      x18

    Другие решения неравенства будем получать переходом на следующий полюс
    и т.д.
    Ответ:
    x>3667.0240249x<795.608339522x > -3667.0240249 \wedge x < -795.608339522
    x>204.988920647x<162.577419823x > -204.988920647 \wedge x < -162.577419823
    x>99.7455667515x<98.1747704247x > -99.7455667515 \wedge x < -98.1747704247
    x>93.4623814443x<91.8915851175x > -93.4623814443 \wedge x < -91.8915851175
    x>87.1791961371x<85.6083998103x > -87.1791961371 \wedge x < -85.6083998103
    x>80.8960108299x<79.3252145031x > -80.8960108299 \wedge x < -79.3252145031
    x>74.6128255228x<73.042029196x > -74.6128255228 \wedge x < -73.042029196
    x>68.3296402156x<66.7588438888x > -68.3296402156 \wedge x < -66.7588438888
    x>62.0464549084x<60.4756585816x > -62.0464549084 \wedge x < -60.4756585816
    x>55.7632696012x<54.1924732744x > -55.7632696012 \wedge x < -54.1924732744
    x>49.480084294x<47.9092879672x > -49.480084294 \wedge x < -47.9092879672
    x>43.1968989869x<41.6261026601x > -43.1968989869 \wedge x < -41.6261026601
    x>36.9137136797x<35.3429173529x > -36.9137136797 \wedge x < -35.3429173529
    x>30.6305283725x<29.0597320457x > -30.6305283725 \wedge x < -29.0597320457
    x>24.3473430653x<22.7765467385x > -24.3473430653 \wedge x < -22.7765467385
    x>18.0641577581x<16.4933614313x > -18.0641577581 \wedge x < -16.4933614313
    x>11.780972451x<10.2101761242x > -11.780972451 \wedge x < -10.2101761242
    x>5.49778714378x<3.92699081699x > -5.49778714378 \wedge x < -3.92699081699
    x>0.785398163397x<2.35619449019x > 0.785398163397 \wedge x < 2.35619449019
    x>7.06858347058x<8.63937979737x > 7.06858347058 \wedge x < 8.63937979737
    x>13.3517687778x<14.9225651046x > 13.3517687778 \wedge x < 14.9225651046
    x>19.6349540849x<21.2057504117x > 19.6349540849 \wedge x < 21.2057504117
    x>25.9181393921x<27.4889357189x > 25.9181393921 \wedge x < 27.4889357189
    x>32.2013246993x<33.7721210261x > 32.2013246993 \wedge x < 33.7721210261
    x>38.4845100065x<40.0553063333x > 38.4845100065 \wedge x < 40.0553063333
    x>44.7676953137x<46.3384916404x > 44.7676953137 \wedge x < 46.3384916404
    x>51.0508806208x<52.6216769476x > 51.0508806208 \wedge x < 52.6216769476
    x>57.334065928x<58.9048622548x > 57.334065928 \wedge x < 58.9048622548
    x>63.6172512352x<65.188047562x > 63.6172512352 \wedge x < 65.188047562
    x>69.9004365424x<71.4712328692x > 69.9004365424 \wedge x < 71.4712328692
    x>76.1836218496x<77.7544181763x > 76.1836218496 \wedge x < 77.7544181763
    x>82.4668071567x<84.0376034835x > 82.4668071567 \wedge x < 84.0376034835
    x>88.7499924639x<90.3207887907x > 88.7499924639 \wedge x < 90.3207887907
    x>95.0331777711x<96.6039740979x > 95.0331777711 \wedge x < 96.6039740979
    x>102.887159405x<107.599548385x > 102.887159405 \wedge x < 107.599548385
    Решение неравенства на графике
    0-60-50-40-30-20-101020304050602-2
    Быстрый ответ [src]
      /   /             pi\     /3*pi            \\
    Or|And|-oo < x, x < --|, And|---- < x, x < oo||
      \   \             4 /     \ 4              //
    (<xx<π4)(3π4<xx<)\left(-\infty < x \wedge x < \frac{\pi}{4}\right) \vee \left(\frac{3 \pi}{4} < x \wedge x < \infty\right)
    Быстрый ответ 2 [src]
          pi     3*pi     
    (-oo, --) U (----, oo)
          4       4       
    x(,π4)(3π4,)x \in \left(-\infty, \frac{\pi}{4}\right) \cup \left(\frac{3 \pi}{4}, \infty\right)