分解因式(a-2b)²-(3a+2b)²(a-2b)²-(3a+2b)²再求值其中a+2b=-3,b=-2

分解因式(a-2b)²-(3a+2b)²(a-2b)²-(3a+2b)²再求值其中a+2b=-3,b=-2
分解因式(a-2b)²-(3a+2b)²
(a-2b)²-(3a+2b)²再求值
其中a+2b=-3,b=-2

分解因式(a-2b)²-(3a+2b)²(a-2b)²-(3a+2b)²再求值其中a+2b=-3,b=-2
(a-2b)²-(3a+2b)²
=[(a-2b)+(3a+2b)].[(a-2b)-(3a+2b)]
=-8a(a+2b)
a+2b=-3 ,b=-2
=>a = 1
(a-2b)²-(3a+2b)²=-8a(a+2b)
=-8(1)(-3)
=24

(a-2b)²-(3a+2b)²= -8 a (a + 2 b)
a+2b=-3，b=-2
(a-2b)²-(3a+2b)²= -8 a (a + 2 b)=-8(-3)=24