(-1/3p+1/2q)(-2/3p-1/4q)快

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(-1/3p+1/2q)(-2/3p-1/4q)快
(-1/3p+1/2q)(-2/3p-1/4q)

(-1/3p+1/2q)(-2/3p-1/4q)快
(-1/3p+1/2q)(-2/3p-1/4q)
=-1/3p(-2/3p-1/4q)+1/2q(-2/3p-1/4q)
=1/9p³+1/12pq-1/3pq-1/8q²
=1/9p³-1/4pq-1/8q²

设大正方形边长是b,小的是a
则4b-4a=96
b-a=24 (1)
b²-a²=960
(b+a)(b-a)=960
b+a=960/(b-a)=40 (2)
(1)+(2)
2b=64
b=32
a=b-24=8
所以大正方形边长是32厘米,小正方形边长是8厘米