72детали - 100%
90-72=18
18/(72/100)=18/0.72=1800/72=25%
7) y=x⁷⁰*sin(x)
y'=(x⁷⁰)'*sin(x)+x⁷⁰*(sin(x))'=70*x⁶⁹*sin(x)+x⁷⁰*cos(x)=
=x⁶⁹*(70*sin(x)+x*cos(x)).
8) y=(x⁵-1)/(x⁶+1)
y'=((x⁵-1)'*(x⁶+1)-(x⁵-1)*(x⁶+1))/(x⁶+1)²=(5x⁴*(x⁶+1)-6x⁵*(5x-1))/(x⁶-1)²=
=(x⁴*(5*(x⁶+1)-6x*(x⁵-1))/(x⁶+1)²=x⁴*(5x⁶+5-6x⁶+6x)/(x⁶+1)²=
=x⁴*(-x⁶+6x+5)/(x⁶+1)².
(∛x+∛y)/(∛x²-∛xy+∛y²)-(∛x-∛y)/[(∛x-∛y)(∛x+∛y)]=
=(∛x+∛y)/(∛x²-∛xy+∛y²)- 1/(∛x+∛y)=(∛x²+2∛xy+∛y²-∛x²+∛xy-∛y²)/(x-y) =3∛xy/(x-y)