4x = (-1)ⁿarcSin(-√2/2) + nπ, n ∈ Z
4x = (-1)ⁿ⁺¹ π/4 + nπ, n ∈ Z
x = (-1)ⁿ⁺¹ π/16 + nπ/4, n ∈ Z
1)
(x-1)/(y+2)=6/7
7*(x-1)=6*(y+2)
(7*(x-1))²=(6*(y+2))²
49*(x-1)²=36*(y+2)²
2)
(x-1)²+(y+2)²=85/9 |×36
36*(x-1)²+36*(y+2)²=85*36/9
36*(x-1)²+36*(y+2)²=85*4
36*(x-1)²+49*(x-1)²=85*4
85*(x-1)²=85*4 |÷85
(x-1)²=4
x-1=2 x₁=3 ⇒
(3-1)/(y+2)=6/7
y+2=2*(7/6)=7/3=2¹/₃
y₁=1/3.
x-1=-2 x₂=-1 ⇒
(-1-1)/(y+2)=6/7
y+2=-2*7/6=-14/6=-7/3=-2¹/₃
y₂=-4¹/₃.
Ответ: x₁=3 y₁=1/3 x₂=-1 y₂=-4¹/₃.
Если х = -4 , ТО У=-7Х
У=-7 * (-4)
У=28
ПОМОЕМУ ТАК )