Cos(2x+10)=-√15+2√3/2√5-4

Question

Cos(2x+10)=-√15+2√3/2√5-4

Answer 1

Cos(2x+10)=(-√5 *√3+2√3)/(2*(√5-2))
cos(2x+10)= - √3(2-√5)/(2*(2-√5)
cos(2x+10)= -√3/2
1)  2x+10=5π/6+2πk
        2x=- 10+5π/6+2πk
         x= - 5+5π/12+πk
2) 2x+10 =- 5π/6+2πk
         x= -5 - 5π/12 + πk
    ответ: x= -5+5π/12+πk,  k∈Z
               x= - 5 - 5π/12+πk,     k∈Z