Tính nhanh nếu có thể: B = -3/5 + 28/5 × (43/56 + 5/24 – 21/63) 23/11/2021 Bởi Amaya Tính nhanh nếu có thể: B = -3/5 + 28/5 × (43/56 + 5/24 – 21/63)
`B = (-3)/5 + 28/5 × (43/56 + 5/24 – 21/63)` `B= (-3)/5 + 28/5 ×108/168` `B= (-3)/5 +3024/840` `B=15/5=3` Bình luận
$\dfrac{-3}{5}+\dfrac{28}{5}×(\dfrac{43}{56}+\dfrac{5}{24}-\dfrac{21}{63})$ $=\dfrac{-3}{5}+\dfrac{28}{5}×\dfrac{9}{14}$ $=\dfrac{-3}{5}+\dfrac{18}{5}$ $=3$ Bình luận
`B = (-3)/5 + 28/5 × (43/56 + 5/24 – 21/63)`
`B= (-3)/5 + 28/5 ×108/168`
`B= (-3)/5 +3024/840`
`B=15/5=3`
$\dfrac{-3}{5}+\dfrac{28}{5}×(\dfrac{43}{56}+\dfrac{5}{24}-\dfrac{21}{63})$
$=\dfrac{-3}{5}+\dfrac{28}{5}×\dfrac{9}{14}$
$=\dfrac{-3}{5}+\dfrac{18}{5}$
$=3$