\(\frac{2}{1x6}+\frac{2}{6x11}+\frac{2}{11x16}+\frac{2}{16x21}+\frac{2}{21x26}\)
= \(\frac{2}{6}+\frac{2}{66}+\frac{2}{176}+\frac{2}{336}+\frac{2}{546}\)
= \(\frac{1}{3}+\frac{1}{33}+\frac{1}{88}+\frac{1}{168}+\frac{1}{273}\)
=\(\frac{5}{13}\)
Mình tự nghĩ đấy .
Chúc bạn học tốt!
25/1x6+25/6x11+25/11x16+25/16x21+25/21x26+25/26x31
giúp mình với ình đang cần gaaops m
C= 55/6x11 + 55/11x16 + 55/16x21 55/21x26 55/ 26x31
C= 55/6x11 + 55/11x16 + 55/16x21 55/21x26 55/ 26x31
28,37-23,18-16,82+71,63 Tính bằng cách thuận tiện
B=1/1x6 + 1/6x11 + 1/16x21 + 1/21x26 + 1/26x31Tính bằng cách thuận tiện
A=5/1x6+5/6x11+5/11x16+5/16x21+...+5/101x106
B=3/1x4+3/4x7+3/7x10+....+3/97x100
C=1/2x7+1/7x12+1/12x17+....+1/97x102
D=1/2+1/6+1/12+1/20+1/30+1/42+1/56+1/72
E=3/2x4+3/4x6+3/6x8+....+3/98x100
Tính:
1, A = 1/1x3 + 1/3x5 + 1/5x7 + ... + 1/2019 x 2021
2, B= 4/11x16 + 4/16x21 + 4/21x26 + ... + 4/61x66
Bài 2 :
E = \(\frac{1}{11x16}+\frac{1}{16x21}+\frac{1}{21x26}+...+\frac{1}{61x66}\)
\(A=\frac{5}{11x16}+\frac{5}{16x21}+\frac{5}{21x26}+....+\frac{5}{61x66}\)
\(C=\frac{2}{3x4}+\frac{2}{4x5}+....+\frac{2}{40x41}+\frac{2}{41x42}\)
Ai nhanh mk tik nha!!!
55/11x16 + 55/16x21 + 55/21x26 + 55/26x31 + 55/31x36 + 55/36x41 = ?
