（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒...（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒成立,

（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒...（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒成立,
（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒...
（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒成立,求a的取值范围

（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒...（1）一元二次不等式ax^2+bx+2>0的解集是（-1/2,-1/3）,求a+b的值?（2）若x∈R,不等式ax^2+ax+1>0恒成立,
ax^2+bx+2>0的解集为-1/2

1,ax平方+bx+2=0的2个根为x1=-1/2,x2=1/3,
韦达定理:x1+x2=-b/a,x1*x2=2/a,
-1/2+1/3=-b/a,-1/2*1/3=2/a,解方程组得:a=-12,b=-2,a+b=-14;
2,
ax^2+ax+1=0无实数解,△=a平方-4*a*1<0,(a-2)平方<4,0

（1）ax^2+bx+2>0的解集是（-1/2，-1/3），知道-1/2和-1/3恰好是ax^2+bx+2=0的两个根，将x=-1/2和x=-1/3代入ax^2+bx+2=0，解得：a=12，b=10，所以a+b=22。
（2）a>0，且图形恒在X轴上方，a²-4a<0 即0＜a ＜4

We open room now! ( Changchun personalized hotel! each of which so much in love .)Is as ' color '!

Changchun , a simple type style hotel , Cost nearly billion yuan ,

100-room h...

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We open room now! ( Changchun personalized hotel! each of which so much in love .)Is as ' color '!

Changchun , a simple type style hotel , Cost nearly billion yuan ,

100-room hotel , 100 rooms there are 100 different rooms face design ,Oakley sunglasses! Ingenuity is really unique , amazing ! Only under these unique alike will a lot of work and on time! All prices are 138 stores ,mulberry bags, holding Violet Liang Yi Qi Zi Qi International VIP members and all affiliated international card companies can also play 6 to 9 fold. Each room is equipped with Lenovo brand (22 -inch LCD monitor) and separate toilet , and a unique Korean LOV tub , some rooms installed in the bedroom is the value of 150,000 yuan each of the 54-inch large LCD TV ,mac blush, Stereo theater experience . Really like their own home , with the impulse to open room ! PS: God, the genius of the design had to exclaim designers , brothers and sisters, to experience! With the open room to go ! ! !

this a beautiful room ! Reproduced all squeak a sound ah ~ !

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