(1)当X2+2X-3=0时,求代数式3X2+6X-4的值.(2)已知(3b-2)2+|2a-b-3|=0,求5(2a-b)-2(6a-2b+4)+(4a-3b-2)的值 (3)若a-b=4,ab=1,求(-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值
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![(1)当X2+2X-3=0时,求代数式3X2+6X-4的值.(2)已知(3b-2)2+|2a-b-3|=0,求5(2a-b)-2(6a-2b+4)+(4a-3b-2)的值 (3)若a-b=4,ab=1,求(-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值](/uploads/image/z/1765430-62-0.jpg?t=%EF%BC%881%EF%BC%89%E5%BD%93X2%2B2X-3%3D0%E6%97%B6%2C%E6%B1%82%E4%BB%A3%E6%95%B0%E5%BC%8F3X2%2B6X-4%E7%9A%84%E5%80%BC.%EF%BC%882%EF%BC%89%E5%B7%B2%E7%9F%A5%283b-2%292%2B%7C2a-b-3%7C%3D0%2C%E6%B1%825%282a-b%29-2%286a-2b%2B4%29%2B%284a-3b-2%29%E7%9A%84%E5%80%BC+%EF%BC%883%EF%BC%89%E8%8B%A5a-b%3D4%2Cab%3D1%2C%E6%B1%82%28-2ab%2B2a%2B3b%29-%283ab%2B2b-2a%29-%28a%2B4b%2Bab%29%E7%9A%84%E5%80%BC)
(1)当X2+2X-3=0时,求代数式3X2+6X-4的值.(2)已知(3b-2)2+|2a-b-3|=0,求5(2a-b)-2(6a-2b+4)+(4a-3b-2)的值 (3)若a-b=4,ab=1,求(-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值
(1)当X2+2X-3=0时,求代数式3X2+6X-4的值.
(2)已知(3b-2)2+|2a-b-3|=0,求5(2a-b)-2(6a-2b+4)+(4a-3b-2)的值
(3)若a-b=4,ab=1,求(-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值
(1)当X2+2X-3=0时,求代数式3X2+6X-4的值.(2)已知(3b-2)2+|2a-b-3|=0,求5(2a-b)-2(6a-2b+4)+(4a-3b-2)的值 (3)若a-b=4,ab=1,求(-2ab+2a+3b)-(3ab+2b-2a)-(a+4b+ab)的值
1.依题意得
X2+2X-3=0
x2+2x=3
原式=3(x2+2x)-4
=3*3-4
=9-4=5
2.依题意得
(3b-2)2=0
3b-2=0
3b=2
b=2/3(三分之2)
|2a-b-3|=0
2a-2/3-3=0
2a=11/3
a=11/6
化简原式=10a-5b-12a+4b-8+4a-3b-2
=2a-4b-10
=2(a-2b-10)
=2*(2/3-11/3-10)
=2*(-13)=-26
3. 化简原式=-2ab+2a+3b-3ab-2b+2a-a-4b-ab
=-6ab+3a-3b
=3(a-b-2ab)
将a-b=4,ab=1带入原式
=3*(4-2)
=3*2=6