cos(4*pi*x/3)=sqrt(3)/2 (уравнение)

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    Найду корень уравнения: cos(4*pi*x/3)=sqrt(3)/2

    Решение

    Вы ввели [src]
                    ___
       /4*pi*x\   \/ 3 
    cos|------| = -----
       \  3   /     2  
    cos(4πx3)=32\cos{\left(\frac{4 \pi x}{3} \right)} = \frac{\sqrt{3}}{2}
    Подробное решение
    Дано уравнение
    cos(4πx3)=32\cos{\left(\frac{4 \pi x}{3} \right)} = \frac{\sqrt{3}}{2}
    - это простейшее тригонометрическое ур-ние
    Это ур-ние преобразуется в
    4πx3=πn+acos(32)\frac{4 \pi x}{3} = \pi n + \operatorname{acos}{\left(\frac{\sqrt{3}}{2} \right)}
    4πx3=πnπ+acos(32)\frac{4 \pi x}{3} = \pi n - \pi + \operatorname{acos}{\left(\frac{\sqrt{3}}{2} \right)}
    Или
    4πx3=πn+π6\frac{4 \pi x}{3} = \pi n + \frac{\pi}{6}
    4πx3=πn5π6\frac{4 \pi x}{3} = \pi n - \frac{5 \pi}{6}
    , где n - любое целое число
    Разделим обе части полученного ур-ния на
    4π3\frac{4 \pi}{3}
    получим ответ:
    x1=3(πn+π6)4πx_{1} = \frac{3 \left(\pi n + \frac{\pi}{6}\right)}{4 \pi}
    x2=3(πn5π6)4πx_{2} = \frac{3 \left(\pi n - \frac{5 \pi}{6}\right)}{4 \pi}
    График
    0-80-60-40-2020406080-1001002-2
    Быстрый ответ [src]
    x1 = 1/8
    x1=18x_{1} = \frac{1}{8}
    x2 = 11/8
    x2=118x_{2} = \frac{11}{8}
    Сумма и произведение корней [src]
    сумма
    0 + 1/8 + 11/8
    (0+18)+118\left(0 + \frac{1}{8}\right) + \frac{11}{8}
    =
    3/2
    32\frac{3}{2}
    произведение
    1*1/8*11/8
    1181181 \cdot \frac{1}{8} \cdot \frac{11}{8}
    =
    11
    --
    64
    1164\frac{11}{64}
    Численный ответ [src]
    x1 = -5.875
    x2 = -49.625
    x3 = 58.375
    x4 = 90.125
    x5 = 7.375
    x6 = -29.875
    x7 = 10.375
    x8 = -1.625
    x9 = 96.125
    x10 = -23.875
    x11 = 97.375
    x12 = -55.625
    x13 = -11.875
    x14 = -76.625
    x15 = 34.375
    x16 = -31.625
    x17 = -91.625
    x18 = 66.125
    x19 = 30.125
    x20 = -10.625
    x21 = 36.125
    x22 = -67.625
    x23 = -47.875
    x24 = 48.125
    x25 = -61.625
    x26 = -89.875
    x27 = -58.625
    x28 = -35.875
    x29 = -94.625
    x30 = 52.375
    x31 = 64.375
    x32 = -46.625
    x33 = 82.375
    x34 = -71.875
    x35 = -34.625
    x36 = 12.125
    x37 = -13.625
    x38 = -79.625
    x39 = 79.375
    x40 = -95.875
    x41 = 84.125
    x42 = -43.625
    x43 = 100.375
    x44 = 13.375
    x45 = -77.875
    x46 = -100.625
    x47 = -70.625
    x48 = -59.875
    x49 = 94.375
    x50 = -52.625
    x51 = -82.625
    x52 = 22.375
    x53 = 76.375
    x54 = -25.625
    x55 = 43.375
    x56 = -65.875
    x57 = -37.625
    x58 = -40.625
    x59 = 73.375
    x60 = 70.375
    x61 = -22.625
    x62 = -19.625
    x63 = -41.875
    x64 = 25.375
    x65 = 42.125
    x66 = 28.375
    x67 = -53.875
    x68 = -97.625
    x69 = 61.375
    x70 = 6.125
    x71 = -28.625
    x72 = -7.625
    x73 = 46.375
    x74 = 85.375
    x75 = -85.625
    x76 = -83.875
    x77 = -88.625
    x78 = 19.375
    x79 = -16.625
    x80 = 24.125
    x81 = 72.125
    x82 = -64.625
    x83 = 88.375
    x84 = 16.375
    x85 = 18.125
    x86 = -73.625
    x87 = 40.375
    x88 = -17.875
    x89 = 67.375
    x90 = 54.125
    x91 = 49.375
    x92 = 60.125
    x93 = 37.375
    x94 = 78.125
    x95 = 1.375
    x96 = 4.375
    x97 = -4.625
    x98 = 31.375
    x99 = 91.375
    x100 = 55.375
    x101 = 0.125
    График
    cos(4*pi*x/3)=sqrt(3)/2 (уравнение) /media/krcore-image-pods/hash/equation/9/69/e4ba99677d3dc2c5174a10c57bf67.png