Rút gọn tổng sau:
\(S=\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+\frac{1}{2^4}+...+\frac{1}{2^{10}}\)
Rút gọn các tổng sau:
\(A=\frac{1}{2}+\left(\frac{1}{2}\right)^2+\left(\frac{1}{2}\right)^3+\left(\frac{1}{2}\right)^4+...+\left(\frac{1}{2}\right)^{2015}\)
\(B=1+\frac{1}{3}+\left(\frac{1}{3}\right)^2+\left(\frac{1}{3}\right)^3+...+\left(\frac{1}{3}\right)^{2016}\)
\(\Rightarrow2A=1+\frac{1}{2}+\left(\frac{1}{2}\right)^2+\left(\frac{1}{2}\right)^3+...+\left(\frac{1}{2}\right)^{2014}\)
\(\Rightarrow2A-A=A=1-\left(\frac{1}{2}\right)^{2015}\)
Với B tương tự nhưng là lấy 3B
Rút gọn các biểu thức sau:
1) A=\(\frac{4^59^4-2.6^9}{2^{10}3^8+6^8.20}\)
2) B=\((\frac{3}{5})^2.5^2-(2\frac{1}{4})^3:\left(\frac{3}{4}\right)^3+\frac{1}{2}\)
1) A = -1 / 3
2) B = -35 / 2
Chúc em làm bài tốt !
Rút gọn biểu thức sau:\(4-\frac{1}{1+\frac{1}{1+\frac{1}{1+\frac{1}{3+\frac{1}{2+\frac{1}{4+\frac{1}{2}}}}}}}\)
Câu 1: Rút gọn: \(A=\left(\frac{3}{2}-\frac{2}{5}+\frac{1}{10}\right):\left(\frac{3}{2}-\frac{2}{3}+\frac{1}{12}\right)\)
Câu 2: Cho \(S=1-\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{2011}-\frac{1}{2012}+\frac{1}{2013}\)và \(P=\frac{1}{1007}+\frac{1}{1008}+...+\frac{1}{2012}+\frac{1}{2013}\). Tính \(\left(S-P\right)^{2013}\)
Rút gọn các biểu thức sau \(\left( {a > 0,b > 0} \right)\):
a) \({a^{\frac{1}{3}}}{a^{\frac{1}{2}}}{a^{\frac{7}{6}}}\);
b) \({a^{\frac{2}{3}}}{a^{\frac{1}{4}}}:{a^{\frac{1}{6}}}\);
c) \(\left( {\frac{3}{2}{a^{ - \frac{3}{2}}}{b^{ - \frac{1}{2}}}} \right)\left( { - \frac{1}{3}{a^{\frac{1}{2}}}{b^{\frac{3}{2}}}} \right)\).
a) \(a^{\dfrac{1}{3}}\cdot a^{\dfrac{1}{2}}\cdot a^{\dfrac{7}{6}}=a^{\dfrac{1}{3}+\dfrac{1}{2}+\dfrac{7}{6}}=a^2\)
b) \(a^{\dfrac{2}{3}}\cdot a^{\dfrac{1}{4}}:a^{\dfrac{1}{6}}=a^{\dfrac{2}{3}+\dfrac{1}{4}-\dfrac{1}{6}}=a^{\dfrac{3}{4}}\)
c) \(\left(\dfrac{3}{2}a^{-\dfrac{3}{2}}\cdot b^{-\dfrac{1}{2}}\right)\left(-\dfrac{1}{3}a^{\dfrac{1}{2}}b^{\dfrac{2}{3}}\right)=\left(\dfrac{3}{2}\cdot-\dfrac{1}{3}\right)\left(a^{-\dfrac{3}{2}}\cdot a^{\dfrac{1}{2}}\right)\left(b^{-\dfrac{1}{2}}\cdot b^{\dfrac{2}{3}}\right)\)
\(=-\dfrac{1}{2}a^{-1}b^{-\dfrac{1}{3}}\)
Bài 1: Tính tổng: \(S=\frac{3}{2\cdot3}+\frac{3}{3\cdot6}+\frac{3}{4\cdot9}+...+\frac{3}{6039\cdot2014}\)
Bài 2: Rút gọn phân số: \(S=\frac{25^{28}+25^{24}+...+25^4+1}{25^{30}+25^{28}+...+25^2+1}\)
Rút gọn biểu thức sau:
a) S =\(1+\frac{1}{3}+\frac{1}{3^2}+\frac{1}{3^3}+...+\frac{1}{3^n}\)
b) A=\(\frac{1}{2}+\frac{1}{2^2}+\frac{1}{2^3}+...+\frac{1}{2^{100}}\)
AI LÀM NHANH MÀ ĐÚNG MIK TICK
rút gọn: A= \(\frac{\frac{3}{2}+\frac{2}{5}+\frac{1}{10}}{\frac{3}{2}+\frac{2}{3}+\frac{1}{12}}\)
\(\frac{72}{55}\)
\(A=\frac{\frac{3}{2}+\frac{2}{5}+\frac{1}{10}}{\frac{3}{2}+\frac{2}{3}+\frac{1}{12}}\)
\(\Rightarrow A=\frac{\frac{15}{10}+\frac{4}{10}+\frac{1}{10}}{\frac{18}{12}+\frac{8}{12}+\frac{1}{12}}=\frac{\frac{20}{10}}{\frac{27}{12}}=\frac{2}{\frac{9}{4}}=2:\frac{9}{4}=2.\frac{4}{9}=\frac{8}{9}\)
! Ko bt có đúng ko nx @@@
~ Học tốt
# Chiyuki Fujito
Rút gọn các biểu thức sau:\(\frac{\frac{1}{2}-\frac{1}{3}+\frac{2}{5}+\frac{1}{8}}{\frac{1}{6}+\frac{3}{20}-\frac{1}{3}+\frac{3}{4}}\)