Решение
log₅x=(log₃125)·log₅3+log₂0,5<span>
log₅x = (log₃5</span>³<span>) * log₅3 + log₂ 2</span>⁻¹
log₅x = 3*(log₃5 * log₅3) - log₂ 2
<span>log₅x = 3 - 1
</span><span>log₅ x = 2
</span>x = 5²
x = 25
Функция:у=2/(2+х)
1)если у равен 5,то
2/(2+х)=5
2+х=2:5
2+х=0.4
х=-1.6
(x-1)²= -4x
x²-2x+1= -4x
x²+2x+1=0
(x+1)²=0
x+1=0
x= -1