A= (1x2x3x...x10)/(1x2x3x...x10)x(1x2x3x...x10)/(2x3x4x...x11)
A=1x 1/11=1/11
bạn nhớ nha
A= (1x2x3x...x10)/(1x2x3x...x10)x(1x2x3x...x10)/(2x3x4x...x11)
A=1x 1/11=1/11
bạn nhớ nha
\(\frac{1^2}{1.2}\) . \(\frac{2^2}{2.3}\) . \(\frac{3^2}{3.4}\) ..... \(\frac{10^2}{10.11}\)
\(\frac{1^2}{1.2}\)\(\frac{2^2}{2.3}\)\(\frac{3^2}{3.4}\).......\(\frac{10^2}{10.11}\)=..........
Đáp án : \(\frac{1}{11}\) các bạn giúp mình cách làm nha
a)A=\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+...+\frac{1}{99.100}< 1\)
b)B=\(\frac{1}{3}+\left(\frac{1}{3}\right)^2+\left(\frac{1}{3}\right)^3+...+\left(\frac{1}{3}\right)^{100}< \frac{1}{2}\)
c)\(\frac{1}{1.2}+\frac{1}{3.4}+\frac{1}{5.6}+...+\frac{1}{49.50}=\frac{1}{26}+\frac{1}{27}+...+\frac{1}{50}\)
d)A=\(\frac{1}{1.2}+\frac{1}{3.4}+...+\frac{1}{99.100}.CMR\frac{7}{12}< A< \frac{5}{6}\)
AI ĐÚNG MINK \(\left(TICK\right)\)CHO (làm đc trên 2 câu)
Tìm số nguyên x, nếu biết:
1)\(4.3^{x-1}+2.3^{x+2}=4.3^6+2.3^9\)
2)\(\frac{5}{3}.8^{x+2}-\frac{3}{5}.8^x=\frac{5}{3}.8^{11}-\frac{3}{5}.8^9\)
3)\(\left(\frac{1}{3}+\frac{1}{6}\right).2^{x+4}-2^x=2^{13}-2^{10}\)
Mấy bn giúp mk nha!!! lm câu nào cg đc hết á, cảm ơn nha!!!!!
:D
Chứng minh rằng: \(\frac{1.2-1}{2!}+\frac{2.3-1}{3!}+\frac{3.4-1}{3!}+...+\frac{99.100-1}{100!}
CMR :
\(\frac{1.2-1}{2!}+\frac{2.3-1}{3!}+\frac{3.4-1}{4!}+....+\frac{99.100-1}{100!}< 2\)
Chứng minh:
a.\(\frac{1}{2!}+\frac{1}{3!}+\frac{1}{4!}+...+\frac{99}{100!}< 1\)
b.\(\frac{1.2-1}{2!}+\frac{2.3-1}{3!}+\frac{3.4-1}{4!}+...+\frac{99.100-1}{100!}< 2\)
1.chứng minh rằng : \(\frac{1}{2}!+\frac{2}{3}!+\frac{3}{4}!+...+\frac{99}{100}!< 1\)
2. Chứng minh rằng :\(\frac{1.2-1}{2}+\frac{2.3-1}{3}+\frac{3.4-1}{4}+...+\frac{99.100-1}{100}< 2\)
Cho A= \(\frac{1}{1.2^2}+\frac{1}{2.3^2}+\frac{1}{3.4^2}+.....+\frac{1}{49.50^2}\)
B=\(\frac{1}{2^2}+\frac{1}{3^2}+\frac{1}{4^2}+....+\frac{1}{50^2}\)
Chứng minh : A < \(\frac{1}{2}\)< B