tìm x
(2/11 * 13 +2/13 * 15 + 2/15 * 17 +2/17 * 9 +2/19*21)* 4+2 - y =19
( * là nhân nha)
Tìm y biết:(2/11*13+2/13*15+2/15*17+2/17*19+2/19*21)*462-y=19
Tìm y biết: (2/11*13 + 2/13*15 + 2/15*17 + 2/17*19 + 2/19*21) * 462 - y = 19
y= 10000000000000000000000000000000000000000000................% luôn nếu két quả này sai thì mình chịu
Tìm x biết (2/11*13+2/13*15+2/15*17+2/17*19+2/19*21)*462 - x = 19
\(\left(\frac{2}{11\times13}+\frac{2}{13\times15}+\frac{2}{15\times17}+\frac{2}{17\times19}+\frac{2}{19\times21}\right)\times462-x=19\)
\(\left(\frac{1}{11}-\frac{1}{13}+\frac{1}{13}-\frac{1}{15}+...+\frac{1}{19}-\frac{1}{21}\right)\times462-x=19\)
\(\left(\frac{1}{11}-\frac{1}{21}\right)\times462-x=19\)
\(\frac{10}{231}\times462-x=19\)
\(20-x=19\)
\(\Rightarrow x=20-19=1\)
Tìm y biết :
( 2/11 * 13 + 2/13* 15 + 2/15 * 17 + 2/17 * 19 + 2/19* 21 ) * 462 - y = 19
(2/11*13+2/13*15+2/15*17+2/17*19+2/19*21)*462-y=19
1+1= ????????????????? đố ai giải được
2/(11*13)+2/(13*15)+2/(15*17)+2/(17*19)+2/(19*21)*462-y=19
( 2 / 11*13 + 2/ 13*15 + 2 /15*17 + 2 /17*19 + 2/19*21 ) *462 - y = 19
\(\Leftrightarrow\left(\dfrac{1}{11}-\dfrac{1}{13}+\dfrac{1}{13}-\dfrac{1}{15}+...+\dfrac{1}{19}-\dfrac{1}{21}\right)\cdot462-y=19\)
\(\Leftrightarrow20-y=19\)
hay y=1
tim y biet [2/11*13+2/13*15+2/15*17+2/17*19+2/19*21]*462-y=19
(2/11×13+2/13×15+2/15×17+2/17×19+2/19×21)×462-x=19
chịu thôi làm sao được chết mất