Найду корень уравнения: cos x/3=0
с изменением знака при 0
Разделим обе части ур-ния на 1/3
pi x1 = -- 2
3*pi x2 = ---- 2
x1 = 76.9690200129499
x2 = 7.85398163397448
x3 = -51.8362787842316
x4 = -92.6769832808989
x5 = -42.4115008234622
x6 = -48.6946861306418
x7 = -32.9867228626928
x8 = 39.2699081698724
x9 = 36.1283155162826
x10 = -26.7035375555132
x11 = -83.2522053201295
x12 = 42.4115008234622
x13 = -4.71238898038469
x14 = -73.8274273593601
x15 = -80.1106126665397
x16 = 83.2522053201295
x17 = 80.1106126665397
x18 = 10.9955742875643
x19 = 4.71238898038469
x20 = 89.5353906273091
x21 = -10.9955742875643
x22 = 23.5619449019235
x23 = -387.986692718339
x24 = -98.9601685880785
x25 = 29.845130209103
x26 = 98.9601685880785
x27 = -64.4026493985908
x28 = -7.85398163397448
x29 = -95.8185759344887
x30 = 58.1194640914112
x31 = -39.2699081698724
x32 = -14.1371669411541
x33 = -67.5442420521806
x34 = -70.6858347057703
x35 = 14.1371669411541
x36 = 26.7035375555132
x37 = 92.6769832808989
x38 = -89.5353906273091
x39 = 67.5442420521806
x40 = 54.9778714378214
x41 = -76.9690200129499
x42 = -86.3937979737193
x43 = 86.3937979737193
x44 = -3623.82712591583
x45 = -17.2787595947439
x46 = 70.6858347057703
x47 = 1.5707963267949
x48 = -20.4203522483337
x49 = -61.261056745001
x50 = 95.8185759344887
x51 = 61.261056745001
x52 = -1.5707963267949
x53 = -29.845130209103
x54 = -54.9778714378214
x55 = 64.4026493985908
x56 = 32.9867228626928
x57 = 17.2787595947439
x58 = 45.553093477052
x59 = 51.8362787842316
x60 = -23.5619449019235
x61 = -2266.65909956504
x62 = -58.1194640914112
x63 = 20.4203522483337
x64 = -36.1283155162826
x65 = -45.553093477052
x66 = 73.8274273593601
x67 = 48.6946861306418