X/y=3/4 ОДЗ: y≠0 y+2≠0 y≠-2
(x-1)/(y+2)=1/2
x=3y/4
(3y/4-1)/(y+2)=1/2
(3y-4)/(4*(y+2))=1/2 |×4
(3y-4)/(y+2)=2
3y-4=2*(y+2)
3y-4=2y+4
y=8 ⇒
x=3*8/4=6.
Ответ: х=6 у=8.
4tgx+3/tgx-7=0
Пусть: tgx= y
Тогда:
4y+3/y-7=0
4t^2-7y+3=0
tgx=1
x=π/4 +πk
tgx= 3/4
x=arctg(0.75)+πk
<span>(a-3)(a-2)-(a-1)^3= a^2 -3a-2a -a^3 +3a^2 -3a +1 =-a^3 +4a^2 -8a +1</span>