chứng minh rằng
1+1/3+1/5+1/7+...+1/99-(1/2+1/4+1/6+...+1/100)=1/51+1/52+...+1/100
Chứng minh rằng: \(\dfrac{1}{3}-\dfrac{2}{3^2}+\dfrac{3}{3^3}-\dfrac{4}{3^4}+...+\dfrac{99}{3^{99}}-\dfrac{100}{3^{100}}< \dfrac{3}{16}\)
cho A = 1/10 + 1/11 + 1/12+ ...+ 1/99 + 1/ 100
chứng Minh Rằng A > 1
Chứng tỏ rằng:
\(\dfrac{1}{3}-\dfrac{2}{3^2}+\dfrac{3}{3^3}-\dfrac{4}{3^4}+...+\dfrac{99}{3^{99}}-\dfrac{100}{3^{100}}< \dfrac{3}{16}\)
Chứng minh rằng : \(\dfrac{1}{3}\) - \(\dfrac{2}{3^2}\) + \(\dfrac{3}{3^3}\) - \(\dfrac{4}{3^4}\) + .......... + \(\dfrac{99}{3^{99}}\) - \(\dfrac{100}{3^{100}}\) < \(\dfrac{3}{16}\)
Chứng minh rằng \(\dfrac{1}{3}\)-\(\dfrac{2}{3^2}\)+\(\dfrac{3}{3^3}\)-\(\dfrac{4}{3^4}\)+.........+\(\dfrac{99}{3^{99}}\)-\(\dfrac{100}{3^{100}}\) < \(\dfrac{3}{16}\)
Cho B = \(\dfrac{1}{100^2}+\dfrac{1}{101^2}+....+\dfrac{1}{199^2}\)
Chứng minh:
\(\dfrac{1}{100}< B< \dfrac{1}{99}\)
Chứng minh rằng :
\(\frac{1}{3}\) - \(\frac{2}{3^2}\) + \(\frac{4}{3^4}\) +...............+\(\frac{99}{3^{99}}\) - \(\frac{100}{3^{100}}\) < \(\frac{3}{16}\)
Giải chi tiết giúp mk nha các bn!! mk cảm ơn nhìu ạ!!
1. 1+ (-2) + 3+ (-4) + . . . +19 + (-20)
2. 1 - 2 + 3- 4 + . . . + 99 - 100
3. -1 + 3 -5 + 7 - . . . +97 - 99
4. 1+ 2 - 3+ 4 + . . . +97 + 98 - 99 - 100