Đề bài: Tìm x
\(3.2^{x+1}+\frac{1}{2}=\frac{49}{2}\)
\(3.2^{x+1}=\frac{49}{2}-\frac{1}{2}\)
\(3.2^{x+1}=24\)
\(2^{x+1}=24\div3\)
\(2^{x+1}=8\)
\(2^{x+1}=2^3\)
\(\Rightarrow x+1=3\)
\(x=2\)
Vậy \(x=2.\)
\(3.2^{2x+1}+\frac{1}{2}=\frac{49}{2}\)
\(\Leftrightarrow3.2^{2x+1}=\frac{48}{2}\)
\(\Leftrightarrow2^{2x+1}=8\)
\(\Leftrightarrow2^{2x+1}=2^3\)
\(\Rightarrow2x+1=3\)
\(\Rightarrow x=1\)
cho p=1/2+1/3+1/4+…+1/47+1/48+1/49+1/50
q=1/49+2/48+3/49+…47/3+48/2+49/1
tính p/q
Mọi người giúp mình câu này với!!!!!! Tính A=(1/49-1/2^2)(1/49-1/3^2).....(1/49-1/100^2)
Tính S/P biết:
S = 1/2 + 1/3 + 1/4 + 1/5 + ... + 1/49 + 1/50
P = 1/49 + 2/48 + 3/47 + ... + 48/2 +49/1
Cho
A=1/2+1/3+...+1/49+1/50
B=1/49+2/48+...+48/2+49/2
Cho S=1/2+1/3+1/4+....+1/48+1/49+1/5000 và P=1/49+2/48+3/47+....+48/2+49/2.Hãy tính S/P
S=1/2+1/3+1/4+....+1/49+1/50,P=1/49+2/48+3/47+....+48/2+49/1,hay tim S/P
Tính
\(\left(\frac{1}{49}-\frac{1}{3^2}\right)\left(\frac{1}{49}-\frac{1}{4^2}\right)...\left(\frac{1}{49}-\frac{1}{49^2}\right)\)
Cho P= 1/2+1/3+1/4+...+1/48+1/49 và Q=1/49+2/48+...+48/2+49/1
hãy tính P/Q
\(\left(\frac{1}{49}-\frac{1}{3^2}\right).\left(\frac{1}{49}-\frac{1}{4^2}\right)...\left(\frac{1}{49}-\frac{1}{49^2}\right)\)=?
\(\left(\frac{1}{49}.\frac{1}{3^2}\right).\left(\frac{1}{49}.\frac{1}{4^2}\right)...\left(\frac{1}{49}-\frac{1}{49^2}\right)\)
AI NHANH MK T
