<span>a+b+c=300 </span>
<span>a/b = 1/9 -> b = 9*a </span>
<span>a*b*c = max </span>
<span>10*a+c = 300 -> c = 300-10*a </span>
<span>9*(300-10*a)*a*a = max </span>
<span>300*a^2-10*a^3 = max -> Derivative: 2*300*a - 30*a^2 = 0-> </span>
<span>a1 = 0 </span>
<span>a2=20 max; </span>
<span>a = 20 </span>
<span>b = 180 </span>
<span>c = 100</span>
(-4a²b⁵)(0,5ab³)³ = (-4a²b⁵)·0,125a³b⁹ = -0,5a⁵b¹⁴
(a² + 15a + 14)(a² + 15a - 14)
По формуле разности квадратов
(a - b)(a + b) = a² - b², получаем:
(a² + 15a)² - 196 = a⁴ + 30a³ + 225a² - 196
А) (100-1)(100+1)=10000+100-100-1=9999
б) (80+3)(80-3)= 160-240+240-9=160-9=151
5a(a+b+c)-5b(a-b-c)-5c(a+b-c)= 5a^2+5ab+5ac-5ab+5b^2+5bc-5ac-5bc+5c^2= 5a^2+5b^2+5c^2
Sin( x+ pi/4) = 1/2;
x+ pi/4 = (-1)^k*pi/6 + pik;
x = (-1)^k* pi/6 - pi/ + pik; k-Z