<span>:5у</span>²<span>+у+у</span>³<span>+5=(5у</span>²+5)+(у+у³)=5(у²+1)+у(у²+1)=(у²+1)(5+у)
Log5(x-4)=2, <span>x - 4 = 5^2,</span>
<span>x - 4=25, </span><span>x = 25+4=29 </span><span>ответ: x = 29.</span>
(a+b)^2 = a^2 + 2ab + b^2 , =>
(0.4x + 1.6y)^2 = 0.16x^2 + 1.28xy + 2,56 y^2
А2-8а+16+а2-16+8а=0
2а2=0
а2=0
а=0