下列命题中,错误的是()A．关于x的一元二次方程,必有两个互为相反数的实根;B．关于x的方程必有两实根；C．关于x的一元二次方程必有一根为零;D．关于x的方程可能没有实根.-九年级数学

更多内容推荐

• --- Any news about the fire?--- Nearly 20 people ______ from the burning building by now.A．rescuedB．
• Whenever Steve sang in the shower, his voice _______ throughout the house.A．has rungB．would ringC．wa
• It is reported that the guy who is going to _________ the lecture spent a year living in the rain fo
• 计算的值为A．B．C．D．-八年级数学
• a与2a的和为（）A．3aB．5aC．3aD．5a-数学
• How did you ___ to paint the whole house in a week?A．tryB．manageC．winD．succeed-高一英语
• （每小题4分，共8分）（1）计算：；（2）解方程：(3x＋2)2－4＝0-九年级数学
• --- May I visit you at 10 o’clock tomorrow morning?--- I’m afraid I ______ a document for my boss th
• The salespeople said they hadn’t overcharged customers, but the police’s report showed that the prac
• At the moment of the car accident, Jason’s life _____ in the blink of an eye.A．changesB．had changedC
• ---The “No.1 Document” is designed to help the rural population increase their incomes.---I believe
• 计算-九年级数学
• ---Anna, you look so tired and wet all over!---Well, you know, all morning I _______ my books to my
• 使式子有意义的的取值范围是_______-九年级数学
• 下列结论正确的是A．B．C．D．-八年级数学
• By the time he arrives in Beijing, we ______ here for two days.A．will have stayedB．will be stayingC．
• --Can I call you back at two o’clock this afternoon? ---- I’m sorry , but then I ______ to Beijing .
• 观察下列各式：，，，，…，请你将猜想的规律用含自然数的代数式表示出来．-九年级数学
• The famous hospital _____ in 1911.A is built B was built C build D builds-高二英语
• 计算：18+8+27-48．-数学
• 计算：=.-九年级数学
• Unfortunately, when I dropped in, Dr. Green ______, so we only had time for a few words.A．just leftB
• 若和都有意义，则的值是A．B．C．D．-八年级数学
• ．-八年级数学
• 若2<x<3，则=_。-九年级数学
• Sun Yang, a young Chinese swimming talent, ___________several gold medals before 2012 London Olympic
• ―Our company will organize a trip to Hongkong next month. I ______ my mother there.―I’d rather you _
• 计算：+20120-九年级数学
• ---It was dangerous to throw that bottle out of the window. You could have hurt someone.---I’m so so
• 如果点P（）关于原点的对称点为（–2，3），则x+y=▲.-九年级数学
• Lin Tao _____ his uncle from the UK tomorrow.A will seeB sawC would seeD had seen-高二英语
• ．若为二次根式，则m的取值为A．m≤3B．m＜3C．m≥3D．m＞3-八年级数学
• If you stick to it, this plan ______ that your company is well prepared to deal with future challeng
• During her childhood Susan read a lot about Chinese history, from which she _________ greatly in her
• 下列计算中，正确的是[]A.|-2|=-2B.C.a3·a2=a5D.2x2-x=x-九年级数学
• 不用计算器计算：23(54+1227)-(24+43)．-数学
• 化简：=（）。-九年级数学
• -八年级数学
• 12-12-213．-数学
• 当时，化简的结果是．-九年级数学
• — I’m afraid that I may miss her at the airport.— Don’t worry. She ______ a bunch of flowers at that
• A completely new situation will______ when a new tool comes into use.A．ariseB．riseC．raiseD．arouse-高二
• As she _________the newspaper, Granny _________asleep.A．read, was fallingB．was reading, fellC．was re
• There are still many people suffering a lot，and we are to do something to________poverty.A．keep outB
• We should spend the money on something that will ________ everyone.A．benefit toB．benefit fromC．benef
• 计算：-九年级数学
• 下列计算中正确的是（）A．3+2=5B．3-2=1C．3+3=33D．34=32-数学
• —How are things going?—The disabled ________ no relatives in Guangzhou ________ by the volunteers, w
• -- May I speak to your manager Mr. Williams at five o’clock tonight?--I’m sorry. Mr. Williams ______
• --Still remember the first time we met in the railway station?--Of course. You ________ for the trai