Решение во вложении----------------
Y=2sinx x=0 y=0 2sinx=0; snx=0 x=πn n∈Z
y=1-cos(2пи+x)=<span>1-cosx x=0 y=1-1=0
1-cosx=0 cosx=1 x=2</span>πn n∈Z
cos(t - π/3) = cost * cos pi/3 + sint *sin pi/3
cos pi/3= 1/2
sin pi/3= <span><span><span><span>√</span></span></span></span>3/2
cos^2t+sin^2t=1 - тригометрическое тождество
sin^2t=1-cos^2t
sint= 15/17 - неподходит, тк t ∈ (π; 3π/2).
sint= -15/17
cos(t - π/3) = cost * cos pi/3 + sint *sin pi/3 = -8/17 * 1/2 + 15/17 * <span><span><span><span>√</span></span></span></span>3/2 =
-8/24+ 15<span><span><span><span>√</span></span></span></span>3/24 = (15<span><span><span><span>√</span></span></span></span>3-8) / 24
Ответ: (15<span><span><span><span>√</span></span></span></span>3-8) / 24
+++++++++++++++++++++++++++++++++
при х=0
(7х+8)(х-1)+(3х-2)(х+2)=18
(7*1+8)(1-1)+(3*1-2)(1+2)=15+3=18