先化简,再求值 (2ab)(-2ab)+(3ab)(3ab+2),期中a-3,b=2快

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先化简,再求值(2ab)(-2ab)+(3ab)(3ab+2),期中a-3,b=2快先化简,再求值(2ab)(-2ab)+(3ab)(3ab+2),期中a-3,b=2快先化简,再求值(2ab)(-2a

先化简,再求值 (2ab)(-2ab)+(3ab)(3ab+2),期中a-3,b=2快
先化简,再求值 (2ab)(-2ab)+(3ab)(3ab+2),期中a-3,b=2

先化简,再求值 (2ab)(-2ab)+(3ab)(3ab+2),期中a-3,b=2快
=2ab[-2ab+(ab)(3ab+2)]
=2ab*ab[-ab+3ab+2]
=2ab*ab[2ab+2]
=4ab*ab[ab+1]
=4a的平方b的平方[ab+1]
代入a=3,b=2
=4*9*4*[3*2+1]
=144*7
=1008

a是=-3吗?
ab=-6
原式=-4a²b²+9a²b²+6ab
=5a²b²+6ab
=5×(-6)²+6×(-6)
=144

(2ab)(-2ab)+(3ab)(3ab+2)
=-4a^2b^2+9a^2b^2+6ab
=5a^2b^2+6ab
=5*9*4+6*3*2
=180+36
=216