. . ...........,.............
Объяснение:
a)(2x²y)³ * (-xy³)²=8x^6y³*x²y^6=8x^8y^9
b)(-x²-7y)²-(x+7y)(7y-x)=x^4-2(-x²)y+49y²-(49y²-x²)=
=x^4+14x²y+49y²-49y²+x²=x^4+14x²y+x²
