31/2.32/2.33/2....60/2=(31.32.33...60)/230
=[(31.32.33...60).(1.2.3...30)]/230.(1.2.3...30)
=[(1.3.5...59).(2.4.6....60)]/(2.4.6...60)=1.3.5...59
CMR: \(\frac{31}{2}.\frac{32}{2}.\frac{33}{2}.....\frac{60}{2}=1.3.5.....59\)
so sánh:
\(P=\frac{31}{2}.\frac{32}{2}.\frac{33}{2}...\frac{60}{2}\)và \(Q=1.3.5.7...59\)
so sánh p và q :
P = 31/2 x 32/2 x 33/2 x .... x 60/2
Q = 1x3x5x7x......x 59
2, so sách M và N
M = 7 x9 + 14 x 27 +21 x 36/21 x 27 + 42 x 81 + 63x 108
N = 37/333
so sanh S=1/30+1/31+1/32+....+1/59+1/60 voi 1/2
Chọn câu đúng:
A. \(\frac{31}{2}\)x \(\frac{32}{2}\)x\(\frac{33}{2}\)x.....x \(\frac{60}{2}\)= 1x2x3x...x60
B.\(\frac{31}{2}\)x \(\frac{32}{2}\)x\(\frac{33}{2}\)x....x \(\frac{60}{2}\)=1x3x5x7...x59
C.\(\frac{31}{2}\)x\(\frac{32}{2}\)x\(\frac{33}{2}\)x....x \(\frac{60}{2}\)=1x3x5x7...x60
D. \(\frac{31}{2}\)x\(\frac{32}{2}\)x\(\frac{33}{2}\)x....x \(\frac{60}{2}\)= 2x4x6x...x60
giúp mik vs mik đag cần gấp ngay bây h
cho s=1/31+1/32+1/33+...+1/59+1/60
chung minh rang : 3/5<s<4/5
tinh A/B, biet
A=1/2*32+1/3*33+1/4*34+...+1/n*(n+30)+...+1/1973*2003
B=1/2*1974+1/3*1975+1/4*1976+...+1/n*(n+1972)+...+1/31*2003.
1 * 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9 * 10 * 11 * 12 * 13 * 14 * 15 * 16 * 17 * 18 * 19 * 20 * 21 * 22 * 23 * 24 * 25 * 26 * 27 * 28 * 29 * 30 * 31 * 32 * 33 * 34 * 35 * 36 * 37 * 38 * 39 * 40 * 41 * 42 * 43 * 44 * 45 * 46 * 47 * 48 * 49 * 50 * 51 * 52 * 53 * 54 * 55 * 56 * 57 * 58 * 59 * 60 * 61 * 62 * 63 * 64 * 65 * 66 * 67 * 68 * 69 * 70 * 71 * 72 * 73 * 74 * 75 * 76 * 77 * 78 * 79 * 80 * 81 * 82 * 83 * 84 * 85 * 86 * 87 * 88 * 89 * 90 * 91 * 92 * 93 * 94 * 95 * 96 * 97 * 98 * 99 * 100 bằng bao nhiêu?
Bài 1: Tính: A=31+33+35+37+...+3111
B=32+34+36+...+3200
C=51+53+55+...+599
D= 52+54+56+...+5100
Bài 2: Chứng minh các phân số sau tối giản với n ϵ N
a) \(\dfrac{2n+1}{n+1}\) b)\(\dfrac{2n+3}{3n+4}\)
