x1 = -re(acos(-3)) + 2*pi - i*im(acos(-3))
x2 = 2*pi - i*im(acos(4))
x3 = re(acos(-3)) + i*im(acos(-3))
x4 = re(acos(4)) + i*im(acos(4))
Объяснение:
x1 = -re(acos(-3)) + 2*pi - i*im(acos(-3))
x2 = 2*pi - i*im(acos(4))
x3 = re(acos(-3)) + i*im(acos(-3))
x4 = re(acos(4)) + i*im(acos(4))
x1 = 3.14159265358979 + 1.76274717403909*i
x2 = 6.28318530717959 - 2.06343706889556*i
x3 = 3.14159265358979 - 1.76274717403909*i
x4 = 2.06343706889556*i
сумма
-re(acos(-3)) + 2*pi - i*im(acos(-3)) + 2*pi - i*im(acos(4)) + i*im(acos(-3)) + re(acos(-3)) + i*im(acos(4)) + re(acos(4))
=
4*pi + re(acos(4))
произведение
(((-re(acos(-3)) + 2*pi - i*im(acos(-3)))*(2*pi - i*im(acos(4*(i*im(acos(-3)) + re(acos(-3*(i*im(acos(4)) + re(acos(4)))
=
-(2*pi - i*im(acos(4)))*(i*im(acos(-3)) + re(acos(-3)))*(i*im(acos(4)) + re(acos(4)))*(-2*pi + i*im(acos(-3)) + re(acos(-3)))
cosx-6sinx=0 |разделим на cosx≠0
1-6tgx=0
tgx=1/6
x=arctg1/6+πn, n∈Z
5sin2x-6cosx=0
10sinxcosx-6cosx=0
2cosx(5sinx-3)=0
cosx=0 или 5sinx-3=0
x=π/2+πn, n∈Z 5sinx=3
sinx=3/5
x=(-1)^n*arcsin(3/5)+2πn, n∈Z
7cos²x-5sinx-5=0
7(1-sin²x)-5sinx-5=0
7-7sin²x-5sinx-5=0
7sin²x+5sinx-2=0
введем замену переменной sinx=t
7t²+5t-2=0
D=25+56=81
t₁=(-5+9)/14=2/7
t₂=(-5-9)/14=-1
вернемся к замене
sinx=2/7
x=(-1)^n*arcsin(2/7)+2πn, n∈Z
sinx=-1
x=-π/2+2πn, n∈Z
