The teacher will be very surprised to see your correct solution 😉
2 4 49*cos (x) + 11*sin(x) = ------ cos(x)
/ / 6 5 4 2 \\ x1 = 2*atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 0//
/ / 6 5 4 2 \\ x2 = 2*atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 1//
/ / / 6 5 4 2 \\\ / / / 6 5 4 2 \\\ x3 = 2*re\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 2/// + 2*I*im\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 2///
/ / / 6 5 4 2 \\\ / / / 6 5 4 2 \\\ x4 = 2*re\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 3/// + 2*I*im\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 3///
/ / / 6 5 4 2 \\\ / / / 6 5 4 2 \\\ x5 = 2*re\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 4/// + 2*I*im\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 4///
/ / / 6 5 4 2 \\\ / / / 6 5 4 2 \\\ x6 = 2*re\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 5/// + 2*I*im\atan\CRootOf\53*x + 22*x - 135*x + 159*x - 22*x - 45, 5///
Eq(x6, 2*re(atan(CRootOf(53*x^6 + 22*x^5 - 135*x^4 + 159*x^2 - 22*x - 45, 5))) + 2*i*im(atan(CRootOf(53*x^6 + 22*x^5 - 135*x^4 + 159*x^2 - 22*x - 45, 5))))
x1 = 64.1204544656937
x2 = -74.1096222922572
x3 = 55.5865531529521
x4 = 5.3210706955154
x5 = -23.8441398348205
x6 = 20.1381573154366
x7 = 32.7045279297958
x8 = -88.9267089121784
x9 = -4.99458391328172
x10 = 26.4213426226162
x11 = -76.3603382978192
x12 = 68.1529237673113
x13 = -80.3928075994368
x14 = -67.8264369850776
x15 = 13.854972008257
x16 = 30.4538119242337
x17 = -99.2423635209755
x18 = -38.6612264547417
x19 = -61.543251677898
x20 = 76.6868250800529
x21 = -26.0948558403825
x22 = -17.5609545276409
x23 = 17.8874413098746
x24 = -82.6435236049988
x25 = 11.604256002695
x26 = 82.9700103872325
x27 = 61.8697384601317
x28 = -32.3780411475621
x29 = 70.4036397728733
x30 = -13.5284852260234
x31 = 7.57178670107746
x32 = -51.2275970691009
x33 = 93.2856649960296
x34 = 2112.43886460624
x35 = -48.9768810635388
x36 = -70.0771529906396
x37 = -55.2600663707184
x38 = 87.00247968885
x39 = -11.2777692204613
x40 = 51.5540838513346
x41 = -63.7939676834601
x42 = 38.9877132369754
x43 = 24.1706266170542
x44 = 99.5688503032092
x45 = 74.4361090744909
x46 = -0.962114611664186
x47 = -30.1273251420001
x48 = -57.5107823762805
x49 = 80.7192943816704
x50 = -92.9591782137959
x51 = -19.8116705332029
x52 = 36.7369972314133
x52 = 36.7369972314133