Question

Tính một cách hợp lý : \(\dfrac{5}{17}.\dfrac{7}{11}+\dfrac{5}{17}.\dfrac{4}{11}+\dfrac{-12}{17}\) là 
A. \(\dfrac{17}{-17}\)                                        B. \(\dfrac{8}{17}\)
C. \(\dfrac{-7}{17}\)                                          D. \(-\dfrac{-7}{17}\)

Answer 1

C.\(-\dfrac{7}{17}\)

Answer 2

`=>` Chọn: `C`

Ta có:

`5/17 . 7/11 + 5/17 . 4/11 + (-12/17) = 5/17 . 1 + (-12/17) = -7/17`

Answer 3

c

Answer 4

\(\dfrac{5}{17}.\dfrac{7}{11}+\dfrac{5}{17}.\dfrac{4}{11}+\dfrac{-12}{17}\\ =\dfrac{5}{17}.\left(\dfrac{7}{11}+\dfrac{4}{11}\right)+\dfrac{-12}{17}\\ =\dfrac{5}{17}.1+\dfrac{-12}{17}=\dfrac{5}{17}+\left(\dfrac{-12}{17}\right)=\dfrac{-7}{17}\\ \Rightarrow ChọnC\)

\(∘Tai\)

Answer 5

c