Tinh nham:
E = 10/5*10 + 10/10*15 + 10/15*20 + 10/20*25 + 10/25*30 +10/30/*35
giup voi may ban UvU dang can gap giup che nha
Tinh nham:
E = 10/5*10 + 10/10*15 + 10/15*20 + 10/20*25 + 10/25*30 +10/30/*35
giup voi may ban UvU dang can gap giup che nha
E=$\frac{10}{5}$x10+$\frac{10}{10}$x15+$\frac{10}{15}$x20+$\frac{10}{20}$x25+$\frac{10}{25}$x30+$\frac{10}{30}$x35
E=2×10+1×15+$\frac{2}{3}$x20+$\frac{1}{2}$x25+$\frac{2}{5}$x30+$\frac{1}{3}$x35
E=20+15+$\frac{40}{3}$+12,5+12+$\frac{35}{3}$
E=(20+15)+($\frac{40}{3}$+$\frac{35}{3}$)+(12,5+12)
E=35+25+24,5
E=84,5
hok tốt
`E = 10/(5×10) + 10/(10×15) + 10/(15×20) + 10/(20×25) + 10/(25×30) + 10/(30×35)`
`⇒ E = 2 × (5/(5×10) + 5/(10×15) + 5/(15×20) + 5/(20×25) + 5/(25×30) + 5/(30×35))`
`⇒ E = 2 × (1/5 – 1/10 + 1/10 – 1/15 + 1/15 – 1/20 + 1/20 – 1/25 + 1/25 – 1/30 + 1/30 – 1/35)`
`⇒ E = 2 × (1/5 – 1/35)`
`⇒ E = 2/5 – 2/35`
`⇒ E = 14/35 – 2/35 = 12/35`