Найду корень уравнения: cos x=0
с изменением знака при 0
pi x1 = -- 2
3*pi x2 = ---- 2
x1 = -168.075206967054
x2 = 76.9690200129499
x3 = 7.85398163397448
x4 = -51.8362787842316
x5 = -92.6769832808989
x6 = -42.4115008234622
x7 = -48.6946861306418
x8 = -32.9867228626928
x9 = 39.2699081698724
x10 = 36.1283155162826
x11 = -26.7035375555132
x12 = -83.2522053201295
x13 = 42.4115008234622
x14 = -4.71238898038469
x15 = -73.8274273593601
x16 = -80.1106126665397
x17 = 83.2522053201295
x18 = 80.1106126665397
x19 = 10.9955742875643
x20 = 4.71238898038469
x21 = 89.5353906273091
x22 = -10.9955742875643
x23 = 23.5619449019235
x24 = -387.986692718339
x25 = -98.9601685880785
x26 = 29.845130209103
x27 = 98.9601685880785
x28 = -64.4026493985908
x29 = -7.85398163397448
x30 = -95.8185759344887
x31 = 58.1194640914112
x32 = -39.2699081698724
x33 = -14.1371669411541
x34 = -67.5442420521806
x35 = -70.6858347057703
x36 = 14.1371669411541
x37 = 26.7035375555132
x38 = 92.6769832808989
x39 = -89.5353906273091
x40 = 67.5442420521806
x41 = 54.9778714378214
x42 = -76.9690200129499
x43 = -86.3937979737193
x44 = 86.3937979737193
x45 = 1.5707963267949
x46 = -17.2787595947439
x47 = 70.6858347057703
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