Mister Exam

1+3sin²x=2sin2x equation

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Numerical solution:

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The solution

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         2                
1 + 3*sin (x) = 2*sin(2*x)
$$3 \sin^{2}{\left(x \right)} + 1 = 2 \sin{\left(2 x \right)}$$
The graph
Rapid solution [src]
             /log(5)      /  ___\\            
x1 = -pi + I*|------ - log\\/ 5 /| + atan(1/2)
             \  2                /            
$$x_{1} = - \pi + \operatorname{atan}{\left(\frac{1}{2} \right)} + i \left(- \log{\left(\sqrt{5} \right)} + \frac{\log{\left(5 \right)}}{2}\right)$$
       /log(5)      /  ___\\            
x2 = I*|------ - log\\/ 5 /| + atan(1/2)
       \  2                /            
$$x_{2} = \operatorname{atan}{\left(\frac{1}{2} \right)} + i \left(- \log{\left(\sqrt{5} \right)} + \frac{\log{\left(5 \right)}}{2}\right)$$
x2 = atan(1/2) + i*(-log(sqrt(5)) + log(5)/2)
Sum and product of roots [src]
sum
        /log(5)      /  ___\\                 /log(5)      /  ___\\            
-pi + I*|------ - log\\/ 5 /| + atan(1/2) + I*|------ - log\\/ 5 /| + atan(1/2)
        \  2                /                 \  2                /            
$$\left(- \pi + \operatorname{atan}{\left(\frac{1}{2} \right)} + i \left(- \log{\left(\sqrt{5} \right)} + \frac{\log{\left(5 \right)}}{2}\right)\right) + \left(\operatorname{atan}{\left(\frac{1}{2} \right)} + i \left(- \log{\left(\sqrt{5} \right)} + \frac{\log{\left(5 \right)}}{2}\right)\right)$$
=
                        /log(5)      /  ___\\
-pi + 2*atan(1/2) + 2*I*|------ - log\\/ 5 /|
                        \  2                /
$$- \pi + 2 \operatorname{atan}{\left(\frac{1}{2} \right)} + 2 i \left(- \log{\left(\sqrt{5} \right)} + \frac{\log{\left(5 \right)}}{2}\right)$$
product
/        /log(5)      /  ___\\            \ /  /log(5)      /  ___\\            \
|-pi + I*|------ - log\\/ 5 /| + atan(1/2)|*|I*|------ - log\\/ 5 /| + atan(1/2)|
\        \  2                /            / \  \  2                /            /
$$\left(\operatorname{atan}{\left(\frac{1}{2} \right)} + i \left(- \log{\left(\sqrt{5} \right)} + \frac{\log{\left(5 \right)}}{2}\right)\right) \left(- \pi + \operatorname{atan}{\left(\frac{1}{2} \right)} + i \left(- \log{\left(\sqrt{5} \right)} + \frac{\log{\left(5 \right)}}{2}\right)\right)$$
=
(-pi + atan(1/2))*atan(1/2)
$$\left(- \pi + \operatorname{atan}{\left(\frac{1}{2} \right)}\right) \operatorname{atan}{\left(\frac{1}{2} \right)}$$
(-pi + atan(1/2))*atan(1/2)
Numerical answer [src]
x1 = 91.5698347820202
x2 = 50.7291298499194
x3 = -56.0850201846647
x4 = -40.3770566846988
x5 = -90.6425390919457
x6 = 100.994612275511
x7 = -18.3859081067509
x8 = -59.2266130367289
x9 = 25.596389048953
x10 = -30.9522787714231
x11 = -21.5275010891603
x12 = -68.6513905620246
x13 = -100.067317246335
x14 = -46.6602419381551
x15 = 35.0211665530579
x16 = -56.0850200842809
x17 = -24.6690933628312
x18 = -2.67794494964284
x19 = -46.6602420281656
x20 = -43.5186496682519
x21 = -12.1027229230545
x22 = -27.8106862171249
x23 = -96.9257248863081
x24 = 41.3043521413617
x25 = 16.1716109577973
x26 = -87.5009468262829
x27 = -15.2443158822842
x28 = 79.0034637011817
x29 = -74.9345763136722
x30 = -43.5186496987085
x31 = -30.9522791676501
x32 = -74.9345759040321
x33 = 28.7379812724486
x34 = 41.3043523624219
x35 = 57.012315483469
x36 = -68.6513905135924
x37 = 47.5875376267079
x38 = 19.3132035944434
x39 = 75.8618713975565
x40 = -62.3682052627098
x41 = 69.5786862043972
x42 = -49.8018348025009
x43 = 79.0034640445039
x44 = -90.6425390891399
x45 = 85.2866495119495
x46 = -8.96113059429183
x47 = 22.4547960691769
x48 = 88.4282418070787
x49 = 85.286649242635
x50 = 66.4370932277241
x51 = -84.3593538407837
x52 = 44.4459446484238
x53 = 19.3132037874613
x54 = 9.88842565730505
x55 = -71.7929833869144
x56 = -34.0938715035767
x57 = 53.8707228175982
x58 = -5.81953763049741
x59 = -52.9434273373617
x60 = -81.2177616138394
x61 = -78.0761686651908
x62 = -84.359354409878
x63 = 63.2955009372529
x64 = -24.6690934906105
x65 = 3.6052404711332
x66 = -2.67794478762447
x67 = 38.1627595483743
x68 = -93.7841319705718
x69 = 6.74683269504696
x70 = -52.9434277407813
x71 = 50.7291300369108
x72 = 60.1539081421637
x73 = 13.0300183579683
x74 = -37.2354644595433
x75 = 35.0211669212533
x76 = 63.2955006908421
x77 = 57.0123151270279
x78 = -96.9257244713711
x79 = 13.0300179792812
x80 = 72.720278427458
x81 = 97.8530199774025
x82 = 31.8795742375181
x83 = -8.96113020628676
x84 = 94.711427005063
x85 = 82.1450567405327
x86 = -65.5097982472926
x87 = 0.463647489982435
x87 = 0.463647489982435