The teacher will be very surprised to see your correct solution 😉
_______________ \/ sin(x)*cos(x) = cos(x)
pi x1 = -- 4
pi x2 = -- 2
3*pi x3 = ---- 2
x3 = 3*pi/2
sum
pi pi 3*pi -- + -- + ---- 4 2 2
=
9*pi ---- 4
product
pi pi 3*pi --*--*---- 4 2 2
=
3 3*pi ----- 16
3*pi^3/16
x1 = -36.9137136796801
x2 = 0.785398163397448
x3 = 51.0508806208341
x4 = 25.9181393921158
x5 = 63.6172512351933
x6 = -80.8960108299372
x7 = -43.1968989868597
x8 = 69.9004365423729
x9 = 13.3517687777566
x10 = 57.3340659280137
x11 = -24.3473430653209
x12 = -99.7455667514759
x13 = -87.1791961371168
x14 = -30.6305283725005
x15 = 7.06858347057703
x16 = 19.6349540849362
x17 = -187.71016105199
x18 = 76.1836218495525
x19 = 32.2013246992954
x20 = -49.4800842940392
x21 = 82.4668071567321
x22 = 38.484510006475
x23 = -93.4623814442964
x24 = 95.0331777710912
x25 = -74.6128255227576
x26 = -62.0464549083984
x27 = -55.7632696012188
x28 = -68.329640215578
x29 = 88.7499924639117
x30 = -5.49778714378214
x31 = 101.316363078271
x32 = 44.7676953136546
x33 = -11.7809724509617
x34 = -18.0641577581413
x34 = -18.0641577581413