2) tg(x-5pi/4)=(tgx-tg5pi/4)/(1+tgx*tg5pi/4)
sin(x+5pi/4)=sinx*cos5pi/4+cosx*sin5pi/4
tg5pi/4=tg(pi+pi/4)=tgpi/4=1, swin5pi/4=sin(pi*pi/4)=-sinpi/4=-(2^1/2)/2 и cos5pi/4=-(2^1/2)/2 = -(2^1/2)/2*(tgx-1)(sinx+cosx)/tgx+1).
tgx=sinx/cosx
-(2^1/2)*(sinx-cosx)/2
5 корень 3* корень 3 = 5 корень 9
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7x-12=27x+24-2x
7x-12=25x+24
18x=-12-24
18x=-36
x=-2
Ответ: x=-2
(a-b)^2
(x+y)^2
(z+t)^2
(m-n)^2
(m+2)^2
(a-6)^2
(1-b)^2
(9+y)^2
(2y-3)^2
(3p+8)^2
(3m+4)^2
(3a-5)^2