Lời giải:
\(\frac{(-3)^7}{7}.\frac{(-3)^8}{9^7}=\frac{(-3)^7.(-3)^8}{7.9^7}=\frac{(-3)^{15}}{7.(3^2)^7}=\frac{-3^{15}}{7.3^{14}}=\frac{-3}{7}\)
Lời giải:
\(\frac{(-3)^7}{7}.\frac{(-3)^8}{9^7}=\frac{(-3)^7.(-3)^8}{7.9^7}=\frac{(-3)^{15}}{7.(3^2)^7}=\frac{-3^{15}}{7.3^{14}}=\frac{-3}{7}\)
1/2 + 2/3 + 3/4 + 4/5 + 5/6 + 6/7 + 7/8 + 8/9 + ........+ 95/96 + 96/97 + 97/98 + 98/99 + 99/100 = ?
1-2-3-4+5-6-7-8+9-10-11-12+...................+97-98-99-100
1-2+3+4+5-6-7×8+9-10-11+12+...+97-98-99+100
Tinh hop li:
a.8/9-1/72-1/56-1/42-1/30-1/20-1/12-1/6-1/2
b.(-1/2)-(-3/5)+(-1/9)+1/127-(+7/18)+4/35-(-2/7)
c.3/5+3/11-(-3/7)+(2/97)-1/35-3/4+(-2/7)
\(S= 1+2-3-4+5+6-7-8+...+97+98-99-100\)
Giúp mình với ạ ! mình đang cần gấp
Rút gọn biểu thức
a) A= 1 - 2 + 3 - 4 + 5 - 6 + 7 - 8 +.....+ 99 - 100
b)B= 1 + 3 - 5 - 7 + 9 + 11 - .... - 397 - 399
c)C=1 - 2 - 3 + 4 + 5 - 6 - 7 + ....... + 97 - 98 - 99 + 100
d)D= 2^2024 - 2^2023 -......- 1
Tính nhanh: 1 - 2 - 3 + 4 + 5 - 6 -7 + 8 +...+97 - 98 - 99 +100
tính tổng:
1+2+3-4-5-6+7+8+9-10-11-12+.....+97+98+99-100-101-102
(1/3+1/3^2+1/3^3+1/3^4).3^5+(1/3^5+1/3^6+1/3^7+1/3^8).3^9+.....+(1/3^97+1/3^98+1/3^99+1/3^100).3^101
Tính
S=1+2-3-4+5+6-7-8+9+10-11-12+........+97+98-99-100
A=2100-299+298-297+......+22-2