giúp e nhanh với e cho 60 điểm
a) 6/7 + (2/11 – 6/7)
b) a . (-1/2) tất cả mũ 3 + 1/2 : 5
c) 25 . (-1/3) tất cả mũ 3 + 1/5 – 2 . (-1/2) tất cả mũ 2 – 1/2
giúp e nhanh với e cho 60 điểm
a) 6/7 + (2/11 – 6/7)
b) a . (-1/2) tất cả mũ 3 + 1/2 : 5
c) 25 . (-1/3) tất cả mũ 3 + 1/5 – 2 . (-1/2) tất cả mũ 2 – 1/2
$a$) `6/7 + (2/11 – 6/7)`
`= 6/7 + 2/11 – 6/7`
`= 2/11`.
$b$) `(-1/2)^3 + 1/2 : 5`
`= – 1/8 + 1/2 . 1/5`
`= -1/8 + 1/10`
`= -5/40 + 4/40`
`= -1/40`.
$c$) `25 . (-1/3)^3 + 1/5 – 2.(-1/2)^2 – 1/2`
`= 25 . {-1}/{27} + 1/5 – 2 . 1/4 – 1/2`
`= -25/27 + 1/5 – 1/2 – 1/2`
`= -25/27 + 2/10 – 5/10 – 5/10`
`= -25/27 + {-8}/10`
`= {-250}/270 + {-216}/270`
`= {-466}/270 = {-233}/{135}`.
Bạn tham khảo nhé!
a) $\dfrac{6}{7}$ + ($\dfrac{2}{11}$ – $\dfrac{6}{7}$)
= $\dfrac{6}{7}$ + $\dfrac{2}{11}$ – $\dfrac{6}{7}$
= [$\dfrac{6}{7}$ + ( – $\dfrac{6}{7}$)] + $\dfrac{2}{11}$
= 0 + $\dfrac{2}{11}$
= $\dfrac{2}{11}$
b) 4 . $\dfrac{-1}{2}$³ + $\dfrac{1}{2}$ : 5
= 4 . ($\dfrac{-1}{8}$) + $\dfrac{1}{2}$ . $\dfrac{1}{5}$
= $\dfrac{-1}{2}$ + $\dfrac{1}{10}$
= $\dfrac{-4}{10}$
c) 25 . $\dfrac{-1}{3}$³ + $\dfrac{1}{5}$ – 2 . $\dfrac{-1}{2}$² – $\dfrac{1}{2}$
= 25 . $\dfrac{-1}{27}$ + $\dfrac{1}{5}$ – 2 . $\dfrac{1}{4}$ – $\dfrac{1}{2}$
= $\dfrac{-25}{27}$ + $\dfrac{1}{5}$ – $\dfrac{1}{2}$ – $\dfrac{1}{2}$
= $\dfrac{-233}{135}$
$FbBinhne2k88$