Найду корень уравнения: cos(x) = -1/2
2*pi x1 = ---- 3
4*pi x2 = ---- 3
x1 = 85.870199198121
x2 = -20.943951023932
x3 = -14.6607657167524
x4 = -90.0589894029074
x5 = -54.4542726622231
x6 = 58.6430628670095
x7 = -35.6047167406843
x8 = -2.0943951023932
x9 = 92.1533845053006
x10 = -27.2271363311115
x11 = 67.0206432765823
x12 = -58.6430628670095
x13 = -41.8879020478639
x14 = -10.471975511966
x15 = 39.7935069454707
x16 = 2.0943951023932
x17 = 41.8879020478639
x18 = -64.9262481741891
x19 = -60.7374579694027
x20 = 83.7758040957278
x21 = -29.3215314335047
x22 = -73.3038285837618
x23 = 48.1710873550435
x24 = 54.4542726622231
x25 = -33.5103216382911
x26 = -39.7935069454707
x27 = 64.9262481741891
x28 = 77.4926187885482
x29 = 46.0766922526503
x30 = -52.3598775598299
x31 = -79.5870138909414
x32 = -23.0383461263252
x33 = -77.4926187885482
x34 = 73.3038285837618
x35 = 90.0589894029074
x36 = -71.2094334813686
x37 = 98.4365698124802
x38 = 117.286125734019
x39 = -85.870199198121
x40 = 16.7551608191456
x41 = 35.6047167406843
x42 = -1623.15620435473
x43 = -67.0206432765823
x44 = 71.2094334813686
x45 = 8.37758040957278
x46 = 416.784625376246
x47 = 27.2271363311115
x48 = 10.471975511966
x49 = 630.412925820352
x50 = -48.1710873550435
x51 = -83.7758040957278
x52 = 33.5103216382911
x53 = -96.342174710087
x54 = 23.0383461263252
x55 = -8.37758040957278
x56 = -16.7551608191456
x57 = 29.3215314335047
x58 = 60.7374579694027
x59 = 4.18879020478639
x60 = -98.4365698124802
x61 = -92.1533845053006
x62 = 52.3598775598299
x63 = 79.5870138909414
x64 = 20.943951023932
x65 = -46.0766922526503
x66 = -4.18879020478639
x67 = 14.6607657167524
x68 = 96.342174710087