计算 (x-3)²-x+3第二题 (2a²-3b²+2)(2-2a²+3b²)

计算 (x-3)²-x+3第二题 (2a²-3b²+2)(2-2a²+3b²)
计算 (x-3)²-x+3
第二题 (2a²-3b²+2)(2-2a²+3b²)

计算 (x-3)²-x+3第二题 (2a²-3b²+2)(2-2a²+3b²)
(x-3)²-x+3
= (x-3)²-(x-3)
= (x²-6x+ 9 -1 ) ( x-3)
= (x² -6x + 8 ) (x-3)
= (x -4 ) (x-2 ) (x-3 )
(2a²-3b²+2)(2-2a²+3b²)
= [2 + (2a²-3b²)] [2 - (2a²-3b²)]
= 2 ² - (2a²-3b²) ²
= 4 - 4a^4 - 9b^4 + 12a²b²