3y²(y³+1 )=3(y^5+y²)=3y^5+3y²
A) (2x²y)^3 *(-xy^3)² =8x^6y^3 *x²y^6 =8x^8y^9
b) (-x-7y)² -(x+7y)(7y-x) =(7y -(-x))² -(49y² -x²) =(7y+x)² -49y² +x² =49y² +14xy +x² -49y² +x² =2x² +14xy
Y`=(2*x∛x²+4/(x*x^(3/4))`=(2*x^(5/2)+4*x(-7/4))`=10*x(2/3)/3-7/(x^11/4).
y`=(√x-∛x)²`=(x^(1/2)-x^(1/3))²`=(x-2*x^(1/6)+x(2/3))`=
=1-5/(3*x(1/6))+2/(3*x^(1/3)).
√40*√10-√20:√5=√400-√4=20-2=18