2sin(3*x)=-1 (уравнение)

Найду корень уравнения: 2sin(3*x)=-1

Вы ввели

2*sin(3*x) = -1

$$2 \sin{\left(3 x \right)} = -1$$

Подробное решение

Дано уравнение
$$2 \sin{\left(3 x \right)} = -1$$
- это простейшее тригонометрическое ур-ние

Разделим обе части ур-ния на 2

Ур-ние превратится в
$$\sin{\left(3 x \right)} = - \frac{1}{2}$$
Это ур-ние преобразуется в
$$3 x = 2 \pi n + \operatorname{asin}{\left(- \frac{1}{2} \right)}$$
$$3 x = 2 \pi n - \operatorname{asin}{\left(- \frac{1}{2} \right)} + \pi$$
Или
$$3 x = 2 \pi n - \frac{\pi}{6}$$
$$3 x = 2 \pi n + \frac{7 \pi}{6}$$
, где n - любое целое число
Разделим обе части полученного ур-ния на
$$3$$
получим ответ:
$$x_{1} = \frac{2 \pi n}{3} - \frac{\pi}{18}$$
$$x_{2} = \frac{2 \pi n}{3} + \frac{7 \pi}{18}$$

Быстрый ответ

     -pi 
x1 = ----
      18 

$$x_{1} = - \frac{\pi}{18}$$

     7*pi
x2 = ----
      18 

$$x_{2} = \frac{7 \pi}{18}$$

Сумма и произведение корней

сумма

  pi   7*pi
- -- + ----
  18    18 

$$- \frac{\pi}{18} + \frac{7 \pi}{18}$$

=

pi
--
3 

$$\frac{\pi}{3}$$

произведение

-pi  7*pi
----*----
 18   18 

$$- \frac{\pi}{18} \frac{7 \pi}{18}$$

=

     2
-7*pi 
------
 324  

$$- \frac{7 \pi^{2}}{324}$$

Численный ответ

x1 = -79.7615468161409

x2 = 1.91986217719376

x3 = 85.6956662729216

x4 = -15.5334303427495

x5 = -28.0998009571087

x6 = -81.8559419185341

x7 = -90.2335223281068

x8 = 10.2974425867665

x9 = 52.1853446346305

x10 = 61.9591884457987

x11 = 50.0909495322373

x12 = 33.3357887130917

x13 = 94.0732466824944

x14 = -83.9503370209273

x15 = -72.0820981073658

x16 = -44.1568300754565

x17 = 39.6189740202713

x18 = -37.873644768277

x19 = 100.356431989674

x20 = 77.3180858633488

x21 = 76.6199541625511

x22 = -26.0054058547155

x23 = -16.929693744345

x24 = -35.7792496658838

x25 = -46.2512251778497

x26 = 70.3367688553715

x27 = -7.15584993317675

x28 = -92.3279174305

x29 = -31.5904594610974

x30 = -21.8166156499291

x31 = -51.1381470834339

x32 = -2.26892802759263

x33 = -65.7989128001862

x34 = -61.6101225953998

x35 = 12.3918376891597

x36 = 47.9965544298441

x37 = 72.4311639577647

x38 = -67.8933079025794

x39 = -17.6278254451427

x40 = -23.9110107523223

x41 = -48.3456202802429

x42 = 91.9788515801012

x43 = -86.0447321233204

x44 = -42.0624349730633

x45 = 64.0535835481919

x46 = -4.36332312998582

x47 = -69.9877030049726

x48 = -11.3446401379631

x49 = 96.1676417848876

x50 = -39.9680398706701

x51 = 41.7133691226645

x52 = -98.6111027376796

x53 = -54.6288055874225

x54 = 54.2797397370236

x55 = 24.2600766027212

x56 = 20.0712863979348

x57 = 30.5432619099008

x58 = 15.8824961931484

x59 = -63.704517697793

x60 = -19.7222205475359

x61 = 4.01425727958696

x62 = -13.4390352403563

x63 = 66.1479786505851

x64 = 68.2423737529783

x65 = 8.20304748437335

x66 = 89.884456477708

x67 = -59.5157274930066

x68 = -77.6671517137477

x69 = 43.8077642250577

x70 = 98.2620368872808

x71 = 26.3544717051144

x72 = 6.10865238198015

x73 = 83.6012711705284

x74 = -88.1391272257137

x75 = 74.5255590601579

x76 = 646.2954220135

x77 = 59.8647933434055

x78 = 87.7900613753148

x79 = 32.637657012294

x80 = -33.6848545634906

x81 = 17.9768912955416

x82 = -0.174532925199433

x83 = -57.4213323906134

x84 = 22.165681500328

x85 = 56.3741348394168

x86 = -75.5727566113545

x87 = 45.9021593274509

x88 = -74.176493209759

x89 = 28.4488668075076

График