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问题 填空题

若抛物线y=2x2-4x+1与x轴两交点分别是（x1，0），（x2，0），则x12+x22=______．

答案

由题意得：y=2x2-4x+1与x轴两交点分别是（x1，0），（x2，0），

∴2x2-4x+1=0，

∴x1+x2=2，x1•x2=

1
2
，

∴x12+x22=x12+x22+2x1x2-2x1x2=（x1+x2）2-2x1x2=4-2×

1
2
=3．

阅读理解

JLetter 1
Whatever I do, I always think about if other people will like it. How can I stop worrying about what they think?                                                         —Eva, 14, Illinois
JLetter 2
My dream is to be on the Olympic team for gymnastics. My dad thinks I started too late and I’ll never be able to make it. He puts me down, but I want his support. What should I do?                                                    —Erica, 9, Texas
JLetter 3
What should I do if I failed a test? I’m afraid to tell my mom because she might get mad at me and I can’t play soccer. And soccer is like the world to me.
—Ashley, 12, Wisconsin
JLetter 4
I just moved and I’m kind of shy, so how do I make new friends?
—Jessica, 11, Canada
Dr. Molly’s Answer ①
You should tell him about your dream and that if you work really hard, it might happen even though you started late. The sooner you tell your dad how you feel, the sooner you’ll be able to work on making your dream come true.
Dr. Molly’s Answer ②
Nobody knows you at your new school. You have nothing to lose, so gather up all your courage and go over to someone who looks friendly and introduce yourself. You can ask that person about your teacher or the other kids in your class to break the ice. Good luck!
Dr. Molly’s Answer ③
It’s better to tell your mom the truth than for her to find out another way. When you tell her, explain why you failed the test. Ask her if she can help you study in the future, so you’ll do better on your tests and also have time for the soccer you love.
Dr. Molly’s Answer ④
Just be yourself and try not to care about what others think. The more you think about it, the worse you will feel. Always act strong and confident. Even if you are a little unsure of something, don’t doubt (怀疑) your abilities to do things right. Just relax.
小题1:Jessica ____________.
A．wonders how to make new friends
B．wishes to be on the Olympic team
C．is afraid to tell her mom about her failing a test
D．keeps worried about what other people think about her
小题2:____________loves playing soccer best.
A．EricaB．EvaC．AshleyD．Jessica
小题3:Erica’s dad doesn’t support her because he thinks she___________.
A．is a little shy and can’t do it wellB．didn’t start at a very early age
C．is too young to be on the teamD．doesn’t work hard
小题4: According to Dr. Molly, Eva should ____________.
A．hold on to her dreamB．always tell the truth
C．be brave to say hello to othersD．be confident of herself
小题5:Which is the correct order of Dr. Molly’s answers to the four letters?
A．①④③②B．③④②①C．②③①④D．④①③②
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单项选择题

足少阳经所属的脏腑是：（）

A、心包

B、胆

C、三焦

D、胃
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