Các câu hỏi tương tự
tinh hop ly
A=1+1/2(1+2)+1/3(1+2+3)+1/4(1+2+3+4)+...+1/16(1+2+3+...+16)
ghi ro cach lam nha
mik tick cho
tinh hop li:
a) 1+2+3...+20
b)1+3+5+...+21
c)2+5+8+...+2018 +2021
d)1*2+2*3+3*4+...+15*16
e)1*2*3+2*3*4+3*4*5+... +13*14*!5
a) Chứng tỏ rằng: B=1/22+1/32+1/42+1/52+1/62+1/72+1/82 < 1
b) Tinh nhanh: A= 1+1/2 (1+2) +1/3 (1+2+3)+1/4(1+2+3+4)+......+1/16(1+2+3+...+16)
tinh nhanh :
Xem chi tiết
a) 5/6 x 11/4 - 5/4 x 23/6
b) 9/16 x 13/4 - 9/4 x 5/16 + 9/16 x 17/
hay tinh tong:
1/1 x 2 + 1/2 x 3 + 1/3 x 4 + .... + 1/n (n + 1)
chung minh:
1/22 + 1/32 + 1/42 + ..... + 1/n2 < 1
giai dum nhe
A=1+1/2(1+2)+1/3(1+2+3)+1/4(1+2+3+4)+...+1/16(1+2+3+4+...+16)
E=1+1/2×(1+2)+1/3×(1+2+3)+1/4×(1+2+3+4)+...+1/16×(1+2+3+4+...+16)
tính hợp lý 1 + 1/2(1+2) +1/3(1+2+3)+1/4(1+2+3+4)+...+1/16(1+2+3+4+...+16)
Tính nhanh
A= 1+ 1/2 (1+2) +1/3 (1+2+3) +1/4 (1+2+3+4) +...+ 1/16 (1+2+3+4+...+16)
1+1/2(1+2)+1/3(1+2+3)+1/4(1+2+3+4)+...+1/16(1+2+3+4+...+16) tính hợp lý