Question

спростить выражение : (5 x²+2y²)² - (5x²+2y²)(5x²-2y²)

Answer 1

(5х²+2у²)(5х²+2у²)-(5х²+2у²)(5х²-2у²)=(5х²+2у²)((5х²+2у²)-(5х²-2у²))=(5х²+2у²)((5х²+2у²-5х²+2у²)=(5х²+2у²)*4у²=20х²у²+8у^4