a) -49.(100-1)
= -49.100+49
= -4900+49
= -4851
b) (-52).(-101)
= (-52). (((-100)-1))
= (-52).(-100)-(-52)
= 5200+52
=5252
a) -49.(100-1)
= -49.100+49
= -4900+49
= -4851
b) (-52).(-101)
= (-52). (((-100)-1))
= (-52).(-100)-(-52)
= 5200+52
=5252
a) -49.(100-1)
= -49.100+49
= -4900+49
= -4851
b) (-52).(-101)
= (-52). (((-100)-1))
= (-52).(-100)-(-52)
= 5200+52
=5252
a) -49.(100-1)
= -49.100+49
= -4900+49
= -4851
b) (-52).(-101)
= (-52). (((-100)-1))
= (-52).(-100)-(-52)
= 5200+52
=5252
1.tính nhanh : cách giải nhé !
a) (-49).99
b)(-52) . (-101)
mình đang vội , nhanh nhé
A = 1 . 2 + 2 . 3 + 3 . 4 + ......... + 98 . 99 / 1 + ( 1 + 2 ) + ( 1 + 2 + 3 ) + ........... + ( 1 + 2 + 3 + ...... + 98 )
B = ( 1 / 51 . 52 ) + 1 / 52 . 53 + ...... + 1 / 100 . 101 ) : ( 1 / 1 . 2 + 1 / 2 . 3 + ........ + 1 / 99 . 100 + 1 / 100 . 101
3+5+7+9+…..+99+101 + 52 . 13
\(A=\frac{100^2+1^2}{100.1}+\frac{99^2+2^2}{99.2}+...+\frac{52^2+49^2}{52.49}+\frac{51^2+50^2}{51.50}\)
\(B=\frac{1}{100.1}+\frac{1}{99.2}+...+\frac{1}{51.50}\)
\(C=\frac{1}{2}+\frac{1}{3}+...+\frac{1}{100}+\frac{1}{101}\)
a) Tính\(\frac{A}{C}\)
b)Tính C-101B
Tính B=1*3+5*7+9*11+...+97*101
C=1*3*5-3*5*7+5*7*9-....-97*99*101
D=1*99+3*97+5*95+...+49*51
E=1*3^3+3*5^3+5*7^3+...+49*51^3
F=1*99^2+2*98^2+3*97^2+...+49*51^2
cho E = \(\frac{100^2+1^2}{100.1}+\frac{99^2+2^2}{99.2}+\frac{98^2+3^2}{98.3}+...+\frac{52^2+49^2}{52.49}+\frac{50^2+49^2}{50.49}\)
F = \(\frac{1}{2}+\frac{1}{3}+...+\frac{1}{100}+\frac{1}{101}\)
Hãy tính E/F
Tính nhanh
a,A=3/1×3 +3/3×5 + ......+ 3/49×51
b,(1+1/1×3)×(1+1/2×4)×(1+1/3×5)×.......×(1+1/99×101)
Tính: \(B=\frac{100^2+1^2}{100\cdot1}+\frac{99^2+2^2}{99\cdot2}+\frac{98^2+3^2}{98\cdot3}+...+\frac{52^2+49^2}{52\cdot49}+\frac{51^2+50^2}{51\cdot50}\)
a)Tìm x thuộc Z,biết:
x-{55-[49+(-28-x)]}=13-{47+[25-(32-x)]}
b)Tính
-1+2+3-4-5+6+7-8-9+...+99-100+101