问题
选择题
设f(x)=3x+3x-8,用二分法求方程3x+3x-8=0在x∈(1,2)内近似解的过程中得f(1)<0,f(1.5)>0,f(1.25)<0,则方程的根落在区间 [ ]
A、(1,1.25)
B、(1.25,1.5)
C、(1.5,2)
D、不能确定
答案
答案:B
设f(x)=3x+3x-8,用二分法求方程3x+3x-8=0在x∈(1,2)内近似解的过程中得f(1)<0,f(1.5)>0,f(1.25)<0,则方程的根落在区间 [ ]
A、(1,1.25)
B、(1.25,1.5)
C、(1.5,2)
D、不能确定
答案:B
Look and choose the proper sentences. 看图,选择合适的句子。 |
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A. An airplane is fast. B. — Mum, may I go on a trip to Beijing? — OK, Li Ming! You work hard in school. You may go. C. We go on a trip by train. D. Jenny and Danny arrive in Shijiazhuang on January 19th. E. I love to go on trips. F. Danny and Jenny leave Canada on January 18th. |