\(t\text{ính}A=1+5+5^2+5^3+...+5^{49}+5^{50}\)
So sánh a và b A = 5 mũ 49 + 1 / 5 mũ 50 + 1
B = 5 mũ 99 + 1 / 5 mũ 50 + 1
A= 3 mũ 49 - 5 / 3 mũ 48 - 5 / 3 mũ 50 - 5 / 3 mũ 49 - 5
Tính:
A = \(1+5+5^2+5^3+...+5^{49}+5^{50}\)
Ta có A=1+5+52+...+550
=>5A=5+52+...+551
=>5A-A=(5+52+...+551)-(1+5+52+...+550)
=>4A=551-1
=>A=(551-1) :4
Chúc bạn học giỏi!
Tính:
A = \(1+5+5^2+5^3+...+5^{49}+5^{50}\)
\(A=1+5+5^2+5^3+...+5^{49}+5^{50}\)
=> \(5\text{A}=5+5^2+5^3+5^4...+5^{49}+5^{50}+5^{51}\)
=> \(5\text{A-A}=5+5^2+5^3+5^4...+5^{49}+5^{50}+5^{51}\) - (\(1+5+5^2+5^3+...+5^{49}+5^{50}\) )
=> \(5\text{A-A}=5+5^2+5^3+5^4...+5^{49}+5^{50}+5^{51}\) - \(1-5-5^2-5^3-...-5^{49}-5^{50}\)
=> \(4\text{A}=5^{51}-1\)
=> \(A=\dfrac{5^{51}-1}{4}\)
Tính:
A = \(1+5+5^2+5^3+...+5^{49}+5^{50}\)
A=1+\((5+5^2+5^3+...+5^{50})\) 5A=\(5+5^2+5^3+...+5^{51}\) 5A=\((1+5+5^2+...+5^{^{ }50})+5^{51}-1\) 5A=A+\(5^{51}-1\) 5A-A=\((5^{51}-1)\) -A A=\(\dfrac{5^{51-1}}{4}\)
Rút gọn: A = 1 + 5 + 52 + 53 + ...... + 549 + 550
\(A=1+5+5^2+5^3+....+5^{49}+5^{50}\)
\(5A=5+5^2+5^3+5^4+.....+5^{50}+5^{51}\)
\(5A-A=5+5^2+5^3+5^4+......+5^{50}+5^{51}-\left(1+5+5^2+5^3+......+5^{49}+5^{50}\right)\)
\(4A=5+5^2+5^3+5^4+......+5^{50}+5^{51}-1-5-5^2-5^3-5^4-.....-5^{49}-5^{50}\)
\(4A=5^{51}-1\)
\(A=\frac{5^{51}-1}{4}\)
A= 1+5+5^2+5^3+........ +5^49+5^50
5A=5+5^2+5^3+........+5^51
5A-A=(5+5^2+5^3+....+5^51)-(1+5+5^2+....+5^50)
4A=5^51-1
A=5^51-1/4
bài này chỉ làm dược vậy không tính dược kết quả
tinh A=1+5+5^2+5^3+...+5^49+5^50
Tính A= 1+ 5 + 5^2 + 5^3 +...+ 5^49 + 5^50
TINH A=1+5+5^2+5^3+...+5^49+5^50
A=1+5+5^2+5^3+...+5^49+5^50
5A= 5+5^2 +...+5^51
ta co : 5A-A= 5^51 - 1
4A= 5^51-1
=> A= 5^51-1/4