Toán a) x+ 4/9.13 + 4/13.17 + 4//17.21 + …… + 4/41.45 = 10 13/09/2021 By Daisy a) x+ 4/9.13 + 4/13.17 + 4//17.21 + …… + 4/41.45 = 10
Câu a `x+ 4/(9.13) + 4/(13.17) + 4/(17.21) + …… + 4/(41.45) = 10` `=>x+ (4/(9.13) + 4/(13.17) + 4/(17.21) + …… + 4/(41.45) )= 10` `=>x+ (1/9-1/13 + 1/13-1/17 + 1/17-1/21 + …… + 1/41-1/45 )= 10` `=>x+ (1/9-1/45 )= 10` `=>x+ 4/45= 10` `=>x=9 41/45` Học tốt!!! #nocopy Trả lời
a.x+ $\frac{4}{9.13}$ +$\frac{4}{13.17}$ +$\frac{4}{17.21}$ +…+$\frac{4}{41.45}$=10 ⇔x+($\frac{4}{9.13}$ +$\frac{4}{13.17}$ +$\frac{4}{17.21}$ +…+$\frac{4}{41.45}$ )=10 ⇔x+($\frac{1}{9}$ -$\frac{1}{13}$ +$\frac{1}{13}$ -$\frac{1}{17}$ +$\frac{1}{17}$ -$\frac{1}{21}$ +…+$\frac{1}{41}$ -$\frac{1}{45}$ )=10 ⇔x+($\frac{1}{9}$ -$\frac{1}{45}$ )=10 ⇔x+$\frac{4}{45}$ =10 ⇔x=10-$\frac{4}{45}$ ⇔x=9$\frac{41}{45}$ . Vậy x=9$\frac{41}{45}$ . Trả lời
Câu a
`x+ 4/(9.13) + 4/(13.17) + 4/(17.21) + …… + 4/(41.45) = 10`
`=>x+ (4/(9.13) + 4/(13.17) + 4/(17.21) + …… + 4/(41.45) )= 10`
`=>x+ (1/9-1/13 + 1/13-1/17 + 1/17-1/21 + …… + 1/41-1/45 )= 10`
`=>x+ (1/9-1/45 )= 10`
`=>x+ 4/45= 10`
`=>x=9 41/45`
Học tốt!!!
#nocopy
a.x+ $\frac{4}{9.13}$ +$\frac{4}{13.17}$ +$\frac{4}{17.21}$ +…+$\frac{4}{41.45}$=10
⇔x+($\frac{4}{9.13}$ +$\frac{4}{13.17}$ +$\frac{4}{17.21}$ +…+$\frac{4}{41.45}$ )=10
⇔x+($\frac{1}{9}$ -$\frac{1}{13}$ +$\frac{1}{13}$ -$\frac{1}{17}$ +$\frac{1}{17}$ -$\frac{1}{21}$ +…+$\frac{1}{41}$ -$\frac{1}{45}$ )=10
⇔x+($\frac{1}{9}$ -$\frac{1}{45}$ )=10
⇔x+$\frac{4}{45}$ =10
⇔x=10-$\frac{4}{45}$
⇔x=9$\frac{41}{45}$ .
Vậy x=9$\frac{41}{45}$ .