3C=1+1/3+1/32+........+1/321
3C-C=2C=1+1/3+1/32+........+1/321-(1/3+1+32+1/33+...+1/322)
2C=1-1/322
C=1/2-1/322/2<1/2
Vậy C<1/2
3C=1+1/3+1/32+........+1/321
3C-C=2C=1+1/3+1/32+........+1/321-(1/3+1+32+1/33+...+1/322)
2C=1-1/322
C=1/2-1/322/2<1/2
Vậy C<1/2
Chứng minh rằng:
A = 1/3 + 1/32 + 1/33 + ..........+ 1/399 < 1/2
B = 3/12x 22 + 5/22 x 32 + 7/32 x 42 +............+ 19/92 x 102 < 1
C = 1/3 + 2/32 + 3/33 + 4/34 +.........+ 100/3100 ≤ 0
a,Cho B = 1/2+1/2^2+1/2^3+...+1/2^99. So sánh B với 1
b, Cho C = 1/3+(1/3)^2+(1/3)^2+(1/3)^3+...+(1/3)^99. CMR C < 1/2
So sánh
A=\(\frac{30^{31}+1}{30^{32}+1}\) và B=\(\frac{30^{32}+1}{30^{33}+1}\)
Cho c= 1/3+1/32+ 1/33+...+1/399
hãy so sánh c với 1/2
a,Cho B = 1/2+1/2^2+1/2^3+...+1/2^99. So sánh B với 1
b, Cho C = 1/3+(1/3)^2+(1/3)^2+(1/3)^3+...+(1/3)^99. CMR C < 1/2
So sánh
A=\(\frac{30^{31}+1}{30^{32}+1}\) và B=\(\frac{30^{32}+1}{30^{33}+1}\)
Help me!Mk đg cần rất gấp ai nhanh mk tick cho
1) So sánh :
a) \(3^{2^3}\) và (32)3 b) (-8)9 và (-32)5 c) 221 và 314
2) Cho \(\dfrac{a}{b}=\dfrac{c}{d}.\) Chứng minh rằng :
a)\(\dfrac{5a+3b}{5c+3d}=\dfrac{5a-3b}{5c-3d}\) b) \(\dfrac{ab}{cd}=\dfrac{\left(a+c\right)^2}{\left(b+d\right)^2}\)
Cho c=1/3+1/32+1/33+...+1/399
Hãy so sánh c với 1/2
cho B= 1/2+ 1/22 +1/23+........+1/299. So sánh B với 1
cho C= 1/3+ ( 1/3)2+(1/3)2+..........+ (1/3)99. CMR C< 1/2