1) S1 = 1 + 2 + 3 +…+ 999 2) S2 = 10 + 12 + 14 + … + 2010 3) S3 = 21 + 23 + 25 + … + 1001 4) S5 = 1 + 4 + 7 + …+79 5) S6 = 15 + 17 + 19 + 21 + … + 151 + 153 + 155 6) S7 = 15 + 25 + 35 + …+115 7) S4 = 24 + 25 + 26 + … + 125 + 126 |
Tính tổng
A, S=1+4+7+...+79. B, S=15+17+19+21+...+151+153
C,S=1+2+3+...+999. D,S=10+12+14+....+2022
E,S = 21+23+25+...+1001. G,S =24+25+26+...+125+126
Tình tổng :
a) 1 + 2 + 3 + ... + 999
b) 10 + 12 + 14 + ... + 2010
c) 21 + 23 + 25 + ... + 1001
d) 24 + 25 + 26 + ... + 125 + 126
e) 1 + 4 + 7 + ... + 79
f) 15 + 17 + 19 + 21 + ... +151 + 153 + 155
g) 15 + 25 + 35 + ... + 115
Giúp mình nha ai nhanh mik tick
Bài 5*. Tính tổng:
S1 = 1 + 2 + 3 + …+ 999
S2 = 21 + 23 + 25 + … + 1001
S3 = 23 + 24 + … + 127 + 128
S4 = 15 + 17 + 19 + 21 + … + 151 + 153 + 155
1. tính tổng
a, 1+2 +3 +... + 999
b, 10+12+14+...+2010
c, 21+23+25+...+1001
d,24+25+26+...+125+126
e, 1+4+7+...+79
f,15+17+19+21+...+151+153+155
g, 15+25+35+...+115
2.tính nhanh
a, 14968+9035+968+35
b, 72x55x216x15
c, 87 x 23 +13x93+70x87
Bài 1: Tính tổng:
a) S1= 1 + 2 + 3 +...+ 999
b) S2= 10 + 12 + 14 +...+ 2010
c) S3= 21 + 23 + 25 +...+ 1001
d) S4= 24 + 25 + 26 +...+ 125 + 126
e) S5= 1 + 4 + 7 +...+ 79
f) S6= 15 + 17 + 19 + 21 +...+ 151 + 153 + 155
g) S7= 15 + 25 + 35 +...+ 115
Tính tổng:
a) S1=1+2+3+...+999
b) S2=10+12+14+...+2010
c) S3=21+23+25+...+1001
d) S4=24+25+26+...+125+126
e) S5=1+4+7+...+79
f) S6=15+17+19+21+...+151+153+155
g) S7=15+25+35+...+115
1.Tính tổng:
S1= 1+2+3+.....+999
S2= 10+12+14+.....+2010
S3= 21+23+25+.....+1001
S4= 24+25+26+.....+125+126
S5= 1+4+7+......+79
S6= 15+17+19+21+......+151+153+155
S6= 15+25+35+.......+115
2. Tìm x:
a) 5^2x=625
b) 9^x-1=9
c) 2^x : 2^5=1
a , S1 = 1 + 2 + 3 + ....... + 999
b , S2 = 10 + 12 + 14 + ...... + 2010
c , S3 = 21 + 23 + 25 + ..... + 1001
d , S4 = 24 + 25 + 26 + ........ + 125 + 126
e , S5 = 1 + 4 + 7 + ..... + 79
f , S6 = 15 + 17 + 19 + 21 + .... + 151 + 153 + 155
g , S7 = 15 + 25 + 35 + .... + 115