E=(1-1/2²)×(1-1/3²)×…×(1/1/10²) Hihi! Giúp mik với ???? 01/09/2021 Bởi Piper E=(1-1/2²)×(1-1/3²)×…×(1/1/10²) Hihi! Giúp mik với ????
E = (1 – $\frac{1}{4}$) x (1 – $\frac{1}{9}$) x (1 – $\frac{1}{16}$) x …. x (1 – $\frac{1}{100}$) . E = $\frac{3}{4}$ x $\frac{8}{9}$ x … x $\frac{99}{100}$ E = $\frac{(1.3)(2.4)(3.5)….(8.10)(9.11)}{(2.2)(3.3)(4.4)(5.5)…(9.9)(10.10)}$ E = $\frac{(1 x 2 x 3 x … 8 x 9)(3 x 4 x 5 x 6 x … x 10 x 11)}{(2 x 3 x 4 x … x 10)(2 x 3 x 4 x … x 10)}$ E = $\frac{1 . 11}{2 .10}$ E = $\frac{11}{20}$ Bình luận
`E = ( 1 – 1/(2^2) ) . ( 1 – 1/(3^2) ) …. ( 1 – 1/(10^2) )` `⇒ E = ( 1 – 1/4 ) . ( 1 – 1/9 ) …. ( 1 – 1/100 )` `⇒ E = 3/4 . 8/9 …. 99/100` `⇒ E = (3 . 8 …. 99)/(4 . 9 …. 100)` `⇒ E = (1 . 3 . 2 . 4 …. 9 . 11)/(2 . 2 . 3 . 3 …. 10 . 10)` `⇒ E = ((1 . 2 …. 9) . (3 . 4 …. 11))/((2 . 3 …. 10) . (2 . 3 …. 10))` `⇒ E = (1 . 11)/(10 . 2)` `⇒ E = 11/20` Vậy `E = 11/20` Bình luận
E = (1 – $\frac{1}{4}$) x (1 – $\frac{1}{9}$) x (1 – $\frac{1}{16}$) x …. x (1 – $\frac{1}{100}$) .
E = $\frac{3}{4}$ x $\frac{8}{9}$ x … x $\frac{99}{100}$
E = $\frac{(1.3)(2.4)(3.5)….(8.10)(9.11)}{(2.2)(3.3)(4.4)(5.5)…(9.9)(10.10)}$
E = $\frac{(1 x 2 x 3 x … 8 x 9)(3 x 4 x 5 x 6 x … x 10 x 11)}{(2 x 3 x 4 x … x 10)(2 x 3 x 4 x … x 10)}$
E = $\frac{1 . 11}{2 .10}$
E = $\frac{11}{20}$
`E = ( 1 – 1/(2^2) ) . ( 1 – 1/(3^2) ) …. ( 1 – 1/(10^2) )`
`⇒ E = ( 1 – 1/4 ) . ( 1 – 1/9 ) …. ( 1 – 1/100 )`
`⇒ E = 3/4 . 8/9 …. 99/100`
`⇒ E = (3 . 8 …. 99)/(4 . 9 …. 100)`
`⇒ E = (1 . 3 . 2 . 4 …. 9 . 11)/(2 . 2 . 3 . 3 …. 10 . 10)`
`⇒ E = ((1 . 2 …. 9) . (3 . 4 …. 11))/((2 . 3 …. 10) . (2 . 3 …. 10))`
`⇒ E = (1 . 11)/(10 . 2)`
`⇒ E = 11/20`
Vậy `E = 11/20`