1.计算 [(3a-7)^2-(a+5)^2]/(4a-24),其中a=32.已知|a+b+1|+a^2b^2+4ab+4=0,求-2a^2-2b^2的值3.已知4a^2+4a+b^2-6b^2+10=0,求ab的值
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![1.计算 [(3a-7)^2-(a+5)^2]/(4a-24),其中a=32.已知|a+b+1|+a^2b^2+4ab+4=0,求-2a^2-2b^2的值3.已知4a^2+4a+b^2-6b^2+10=0,求ab的值](/uploads/image/z/8413121-65-1.jpg?t=1.%E8%AE%A1%E7%AE%97+%5B%283a-7%29%5E2-%28a%2B5%29%5E2%5D%2F%EF%BC%884a-24%29%2C%E5%85%B6%E4%B8%ADa%3D32.%E5%B7%B2%E7%9F%A5%7Ca%2Bb%2B1%7C%2Ba%5E2b%5E2%2B4ab%2B4%3D0%2C%E6%B1%82-2a%5E2-2b%5E2%E7%9A%84%E5%80%BC3.%E5%B7%B2%E7%9F%A54a%5E2%2B4a%2Bb%5E2-6b%5E2%2B10%3D0%2C%E6%B1%82ab%E7%9A%84%E5%80%BC)
1.计算 [(3a-7)^2-(a+5)^2]/(4a-24),其中a=32.已知|a+b+1|+a^2b^2+4ab+4=0,求-2a^2-2b^2的值3.已知4a^2+4a+b^2-6b^2+10=0,求ab的值
1.计算 [(3a-7)^2-(a+5)^2]/(4a-24),其中a=3
2.已知|a+b+1|+a^2b^2+4ab+4=0,求-2a^2-2b^2的值
3.已知4a^2+4a+b^2-6b^2+10=0,求ab的值
1.计算 [(3a-7)^2-(a+5)^2]/(4a-24),其中a=32.已知|a+b+1|+a^2b^2+4ab+4=0,求-2a^2-2b^2的值3.已知4a^2+4a+b^2-6b^2+10=0,求ab的值
1.计算 [(3a-7)^2-(a+5)^2]/(4a-24),其中a=3
[(3a-7)^2-(a+5)^2]/(4a-24)
=(3a-7-a-5)(3a-7+a+5)/4(a-6)
=2(a-6)*2(2a-1)/4(a-6)
=2a-1
=6-1=5
2.已知|a+b+1|+a^2b^2+4ab+4=0,求-2a^2-2b^2的值
|a+b+1|+a^2b^2+4ab+4
=|a+b+1|+(ab+2)^2
=0
∵|a+b+1|>=0 (ab+2)^2>=0
∴a+b=-1 ab=-2
a^2+b^2=(a+b)^2-2ab=1+4=5
-2a^2-2b^2=-2(a^2+b^2)= -2*5= -10
3.已知4a^2+4a+b^2-6b^2+10=0,求ab的值
4a^2+4a+b^2-6b+10=0
4a^2+4a+1+b^2-6b+9=0
(2a+1)^2+(b-3)^2=0
a=-1/2
b=3
ab= -3/2