tính
a,(1+8/10).(1+8/22).(1+8/36).(1+8/52)................(1+8/8352)
b,2.4+3.5+4.6+5.7+6.8+...............+97.99+98.100
tìm GTNN của A= |x^2+5| +(2y-3)\(^4\)
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2A=2+2^2+2^3-2^4+...+2^2017
2A+A=2+1+2^2+2+2^2+2^3-2^3+2^4-2^4+...+2^2017-2^2016
3A=1+2^2+2^3+2^2017
A=(1+2^2+2^3+2^2017)/3
Minh giai 1 bai thoi nha
Nho k cho minh voi
a) \(A=1-2+2^2-2^3+2^4-2^5+.................+2^{2016}\)
\(\Rightarrow2A=2\left(1-2+2^2-2^3+2^4-2^5+............+2^{2016}\right)\)
\(\Rightarrow2A=2-2^2+2^3-2^4+2^5-2^6+...........+2^{2017}\)
\(\Rightarrow2A-A=\left(2-2^2+2^3-2^4+.........+2^{2016}\right)-\left(1-2+2^3+2^4-2^5+.....+2^{2017}\right)\)\(\Rightarrow A=2^{2017}-1\)
Câu a xong đã, câu b tính sau :P
Answer:
\(\left(1+\frac{8}{10}\right).\left(1+\frac{8}{22}\right).\left(1+\frac{8}{36}\right)...\left(1+\frac{8}{8352}\right)\)
\(=\frac{18}{10}.\frac{30}{22}.\frac{44}{36}...\frac{8360}{8352}\)
\(=\frac{2.9.3.10.4.11....88.95}{1.10.2.11.3.12...87.96}\)
\(=\frac{\left(2.3.4...8\right).\left(9.10.11...95\right)}{\left(1.2.3...87\right).\left(10.11...96\right)}\)
\(=\frac{9.88}{96}\)
\(=\frac{3}{4}\)