The teacher will be very surprised to see your correct solution 😉
/x\ 1 - tan|-| \2/ /x\ ---------- = 2*sin|-| /x\ \2/ 1 - cot|-| \2/
a1 = 1 - tan(x/2)
b1 = 1 - cot(x/2)
a2 = 2
b2 = 1/sin(x/2)
1+tan+x/2)/sinx/2 = 2 - 2*cot(x/2)
1+tan+x/2)/sinx/2 = 2 - 2*cotx/2
-8*pi x1 = ----- 3
-4*pi x2 = ----- 3
4*pi x3 = ---- 3
8*pi x4 = ---- 3
x4 = 8*pi/3
sum
8*pi 4*pi 4*pi 8*pi - ---- - ---- + ---- + ---- 3 3 3 3
=
0
product
-8*pi -4*pi 4*pi 8*pi -----*-----*----*---- 3 3 3 3
=
4 1024*pi -------- 81
1024*pi^4/81
x1 = -69.1150383789755
x2 = -100.530964914873
x3 = 33.5103216382911
x4 = -25.1327412287183
x5 = -75.398223686155
x6 = -33.5103216382911
x7 = -50.2654824574367
x8 = -46.0766922526503
x9 = 81.6814089933346
x10 = 50.2654824574367
x11 = -43.9822971502571
x12 = -37.6991118430775
x13 = -16.7551608191456
x14 = 108.908545324446
x15 = 25.1327412287183
x16 = -18.8495559215388
x17 = -8.37758040957278
x18 = -92.1533845053006
x19 = -96.342174710087
x20 = 31.4159265358979
x21 = -56.5486677646163
x22 = 18.8495559215388
x23 = -232.477856365645
x24 = -6.28318530717959
x25 = -62.8318530717959
x26 = -29.3215314335047
x27 = 12.5663706143592
x28 = -54.4542726622231
x29 = 69.1150383789755
x30 = 58.6430628670095
x31 = 56.5486677646163
x32 = 6.28318530717959
x33 = 83.7758040957278
x34 = 37.6991118430775
x35 = -83.7758040957278
x36 = 96.342174710087
x37 = 92.1533845053006
x38 = -31.4159265358979
x39 = 41.8879020478639
x40 = 100.530964914873
x41 = 71.2094334813686
x42 = 94.2477796076938
x43 = 16.7551608191456
x44 = -12.5663706143592
x45 = 54.4542726622231
x46 = -79.5870138909414
x47 = -94.2477796076938
x48 = 67.0206432765823
x49 = 43.9822971502571
x50 = 75.398223686155
x51 = -41.8879020478639
x52 = 62.8318530717959
x53 = 87.9645943005142
x54 = -4.18879020478639
x55 = -20.943951023932
x56 = -81.6814089933346
x57 = -87.9645943005142
x58 = -71.2094334813686
x59 = 4.18879020478639
x60 = 46.0766922526503
x61 = 8.37758040957278
x61 = 8.37758040957278