Sinx(sinx-10)=0
sinx=0⇒x=πn,n∈z
sinx=10>1 нет решения
Тут просто треугольники СDE и CAB подобны, значит DC/AC=DE/AB , AB=4*15/12=5
Sin2x + 1 = Cosx + 2Sinx
Sin2x - 2Sinx + 1 - Cosx = 0
(2SinxCosx - 2Sinx) + (1 - Cosx) = 0
2Sinx(Cosx - 1) - (Cosx - 1) = 0
(Cosx - 1)(2Sinx - 1) = 0
![\left[\begin{array}{ccc}Cosx-1=0\\2Sinx-1=0\end{array}\right\\\\\\\left[\begin{array}{ccc}Cosx=1\\Sinx=\frac{1}{2} \end{array}\right\\\\\\\left[\begin{array}{ccc}x=2\pi n,n\in Z \\x=(-1)^{n}arcSin\frac{1}{2}+\pi n,n\in Z \end{array}\right\\\\\\\left[\begin{array}{ccc}x=2\pi n,n\jn Z \\x=(-1)^{n}\frac{\pi }{6}+\pi n,n\in Z \end{array}\right](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7DCosx-1%3D0%5C%5C2Sinx-1%3D0%5Cend%7Barray%7D%5Cright%5C%5C%5C%5C%5C%5C%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7DCosx%3D1%5C%5CSinx%3D%5Cfrac%7B1%7D%7B2%7D%20%5Cend%7Barray%7D%5Cright%5C%5C%5C%5C%5C%5C%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%3D2%5Cpi%20n%2Cn%5Cin%20Z%20%5C%5Cx%3D%28-1%29%5E%7Bn%7DarcSin%5Cfrac%7B1%7D%7B2%7D%2B%5Cpi%20n%2Cn%5Cin%20Z%20%20%20%5Cend%7Barray%7D%5Cright%5C%5C%5C%5C%5C%5C%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%3D2%5Cpi%20n%2Cn%5Cjn%20Z%20%5C%5Cx%3D%28-1%29%5E%7Bn%7D%5Cfrac%7B%5Cpi%20%7D%7B6%7D%2B%5Cpi%20n%2Cn%5Cin%20Z%20%20%20%5Cend%7Barray%7D%5Cright)
Ответ: х=+-6. Ваше решение. Приятной учебы