\(A=2^0+2^1+2^2+2^3+2^4+...+2^{100}\)
\(B=2^{101}\)
1, cho a^100+b^100=a^101+b^101=a^101+b^101=a^102+b^102.CM a+b/b=a^2+b^2/a^2b^2
2,tính gtbt:A= x/xy+x+1+y/y+1+yz+z/1+z+xz
3, cho a,b,c,d>0 TM:a^2+b^2=1 và a^4/b+c^4/d=1/b+d CM:a^2016/b^1003+c^2006/d^1003=2/(b+d)^1003
\(A=1+\frac{3}{2^3}+\frac{4}{2^4}+...+\frac{100}{2^{100}}\)
\(\frac{A}{2}=\frac{1}{2}+\frac{3}{2^4}+\frac{4}{2^5}+....+\frac{100}{2^{101}}\)\(A-\frac{A}{2}=\left(1+\frac{3}{2^3}+....+\frac{100}{2^{100}}\right)-\left(\frac{1}{2}+\frac{3}{2^4}+.....+\frac{100}{2^{101}}\right)\)
\(\frac{A}{2}=\frac{1}{2}+\frac{3}{2^3}+\frac{1}{2^4}+\frac{1}{2^5}+....+\frac{1}{2^{100}}-\frac{100}{2^{101}}\)
\(\frac{A}{2}=\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+\frac{1}{2^4}+....+\frac{1}{2^{100}}-\frac{1}{2^{101}}\)
\(\frac{A}{2}=\left(1-\left(\frac{1}{2}\right)^{101}\right).2-\frac{100}{2^{101}}\)
\(\frac{A}{2}=\frac{2^{101}-1}{2^{100}}-\frac{100}{2^{101}}\)
\(A=\frac{2^{101}-1}{2^{99}}-\frac{100}{2^{100}}\)
A = 1 . 2 + 2 . 3 + 3 . 4 + ......... + 98 . 99 / 1 + ( 1 + 2 ) + ( 1 + 2 + 3 ) + ........... + ( 1 + 2 + 3 + ...... + 98 )
B = ( 1 / 51 . 52 ) + 1 / 52 . 53 + ...... + 1 / 100 . 101 ) : ( 1 / 1 . 2 + 1 / 2 . 3 + ........ + 1 / 99 . 100 + 1 / 100 . 101
Tính
a) (x-1/2)+(x-1/4)+(x-1/8)+...+(x-1/512)
Tìm x
a) (x-1/1×2)+(x-1/2×3)+...+(x-1/100×101)
b) (x-1)+(x-2)+(x-3)+...+(x-101)=5050
c) x+1/2+1/3+1/4+...+1/100=3/2+4/3+5/4++...+101/100
tính
a. A= 101+100+99+98+....+3+2+1/101-100+99-98+...+3-2+1
b,B= 3737.43-4343.37/2+4+6+...+100
Tính các tổng sau:
a) A = 1*2+2*3+3*4+...+2014*2015
b) B = 101^2+102^2+...+199^2+200^2
c) C = 1*3+2*4+3*5+4*6+...+99*101+100*102
cho mi sửa lại:
\(a) A = 1^2+2^3+3^4+...+2014^{2015} b) B = 101^2+102^2+...+199^2+200^2 c) C = 1^3+2^4+3^5+4^6+...+99^{101}+100^{102}\)
dấu 8 là nhân còn dấu ^ là mũ ạ
a. A= (101+100+99+98+97+....+3+2+1) : (101-100+99-98+....+3-2+1)
b, B=(3737.43 -4343.37) : (2+4+6+....+100)
\(A =\)\(\dfrac{101+100+99+98+...+3+2+1}{101-100+99-98+...+3-2+1}\)
\(B=\) \(\dfrac{3737.43-4343.37}{2+4+6+...+100}\)
Làm cách lớp 6 thôi ah
\(A=\dfrac{101\cdot\dfrac{102}{2}}{\left(101-100\right)+99-98+...+3-2+1}\)
\(=\dfrac{101\cdot51}{1+1+...+1}=\dfrac{101\cdot51}{51}=101\)
\(B=\dfrac{37\cdot43\left(101-101\right)}{2+4+...+100}=0\)
a, \(A=\dfrac{101+100+99+98+...+3+2+1}{101-100+99-98+...+3-2+1}\)
Ta có: \(T=101+100+99+98+...+3+2+1\) \(=\dfrac{\left(101+1\right).101}{2}\)
\(=\dfrac{102.101}{2}\Leftrightarrow51.101\)
\(M=101-100+99-98+...+3-2+1\)
Ta có: \(101:2=50\) (dư \(1\))
\(\Rightarrow M=\left(101-100\right)+\left(99-98\right)+...+\left(3-2\right)+1\)
Có \(50\) dấu ngoặc tròn "\(\left(\right)\)"
\(\Rightarrow M=1+1+...+1+1=51.1=51\)
\(M\) có \(51\) số \(1\)
\(\Rightarrow A=\dfrac{T}{M}=\dfrac{51.101}{51}=101\)
Vậy \(A=101\)
b, \(B=\dfrac{3737.43-4343.37}{2+4+6+...100}\)
Ta có: \(T=3737.43-4343.37\)
\(T=37.101.43-43.101.37\)
\(T=0\)
\(\Rightarrow\) \(B=\dfrac{T}{2+4+6+...+100}=\dfrac{0}{2+4+6+...+100}\) \(=0\)
Vậy \(B=0\)
Bài 1:
a, A=1+(-2)+(-3)+4+5+(-6)+(-7)+8+...+99-100-101+102+103
b, B=1+(-3)+5+(-7)+...+97+(-99)+101
Bài 2:
a,|x+2|-x=2
b,|x-3|+x-3=0
c, |x+1|+|x+2|=1
d,|x-5|+x-8=6
1
b;
B=1+ (7-5) + (11-9) + ...+(101-99)
B=1+2+2+..+2
B=1+25.2=51
2.
a.
ĐK : x+2 >=0 => x>=-2
\(\left|x+2\right|-x=2\\ \Rightarrow\left|x+2\right|=2+x\\ \Rightarrow\left[{}\begin{matrix}x+2=x+2\\x+2=-x-2\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}0x=0\\2x=-4\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}0x=0\\x=-2\end{matrix}\right.\)
Vậy x=-2
2.
d;
\(\left|x-5\right|\)=14-x
\(\Leftrightarrow\left[{}\begin{matrix}x-5=14-x\\x-5=x-14\end{matrix}\right.\)
em giải 2 cái này ra để tìm x