Thực hiện tính:
M = 1 + 1/2. (1+ 2) + 1/3. (1 +2 + 3) + ... + 1/16. ( 1+ 2 +3 +... +16)
Thực hiện tính
M=1+1/2(1+2)+1/3(1+2+3)+1/4(1+2+3+4)+...+1/16(1+2+3+...+16)
Thực hiện phép tính:
M=1+1/2(1+2)+1/3(1+2+3)+1/4(1+2+3+4)+...+1/16(1+2+3+...+16)
Thực hiện phép tính:
M = 1 + (-2) + 3 + (-4) + .... + 2021 + (-2022) + 2023
M=(-1)+(-1)+...+(-1)+2023
=-1011+2023
=1012
Bài 1:Thực hiện phép tính:3√49-1,5(√4-1/3)2+1/4:(-1/√16+1/2)
a) Tính tổng: S = (-1/7)0 + (-1/7)1 + (-1/7)2 +...+ (-1/7)2007
b) Thực hiện phép tính: M = 1 + 1/2*(1+2) + 1/3*(1+2+3) + 1/4*(1+2+3+4) +...+ 1/16*(1+2+3+...+16)
a) \(S=\left(-\frac{1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+\left(-\frac{1}{7}\right)^2+...+\left(-\frac{1}{7}\right)^{2007}\)
\(=1+\left(-\frac{1}{7}\right)+\left(-\frac{1}{7}\right)^2+...+\left(-\frac{1}{7}\right)^{2007}\)
=> 7S = \(7+\left(-1\right)+\left(-\frac{1}{7}\right)+...+\left(-\frac{1}{7}\right)^{2006}\)
Lấy 7S trừ S ta có :
7S - S = \(7+\left(-1\right)+\left(-\frac{1}{7}\right)+...+\left(-\frac{1}{7}\right)^{2006}-\left[1+\left(-\frac{1}{7}\right)+\left(-\frac{1}{7}\right)^2+...+\left(-\frac{1}{7}\right)^{2007}\right]\)
6S = \(7-1-1+\left(\frac{1}{7}\right)^{2007}=5+\left(\frac{1}{7}\right)^{2007}\Rightarrow S=\frac{5+\left(\frac{1}{7}\right)^{2007}}{6}\)
Bài 1: Thực hiện phép tính.
A) 3: ( -1/2 )2 + 1/9 x Căn 36
B) 81 x ( 1/3)3 + 1/3
C) Căn 12 + Căn 27 - Căn 3
D) -32 - ( 1/2)-2 : 2 + (2/3)0 : (3/4)-1
E) 3/4 - ( -1/2 )2
F) 15/16 : (-2 2/3) + 15/16 : ( -1 3/5 )
G) 3/5 + -1/4 + 3/20
H) 3: ( -3/2)2 + 1/9 x căn 36
I) 272 x 85/ 66 x 323
J) (0.8)5/ (0.4)6
K) 272/ 242
L) (0.125)3 x 83
M) (-39)4 : 134
N) (0.6)5/ (0.2)6
O) ( 3/7 + 1/2 )2
P) 2:(1/2 - 2/3 )2
Q) 9x (-1/3)3 + 1/3
c: \(=2\sqrt{3}+3\sqrt{3}-\sqrt{3}=4\sqrt{3}\)
Thực hiện phép tính
P= \(1+\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}\left(1+2+3+4\right)+.....+\frac{1}{16}\left(1+2+3+...+16\right)\)
\(1+\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}\left(1+2+3+4\right)+...+\frac{1}{16}\left(1+2+3+...+16\right)\)
\(=1+\frac{1}{2}.\frac{2.3}{2}+\frac{1}{3}.\frac{3.4}{2}+\frac{1}{4}.\frac{4.5}{2}+...+\frac{1}{16}.\frac{16.17}{2}\)
\(=\frac{2}{2}+\frac{3}{2}+\frac{4}{2}+\frac{5}{2}+...+\frac{17}{2}\)
\(=\frac{\frac{17.18}{2}-1}{2}=76\)
Thực hiện phép tính
M=\(1+\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}\left(1+2+3+4\right)+...+\frac{1}{16}\left(1+2+3+...+16\right)\)
Thực hiện tính
M=\(1+\dfrac{1}{2}\cdot\left(1+2\right)+\dfrac{1}{3}\cdot\left(1+2+3\right)+\dfrac{1}{4}\cdot\left(1+2+3+4\right)+...+\dfrac{1}{16}\cdot\left(1+2+3+...+16\right)\)