S=1/1*2+1/2*3+1/3*4+...+1/99*100
S=1/1*3+1/3*5+1/5*7+....+1/99*101
câu 7: tính T=(1/2-1/3)(1/2-1/5)(1/2-1/7)....(1/2-1/99)
Tính:
A=( 1/2 - 1/3 ).( 1/2 - 1/5 ).( 1/2 - 1/7 )...( 1/2 - 1/99 )
Tính:
A=( 1/2 - 1/3 ).( 1/2 - 1/5 ).( 1/2 - 1/7 )...( 1/2 - 1/99 )
.·´¯`(>▂<)´¯`·.
Tính giá trị biểu thức :
A = ( 3 - 1 / 4 + 2 /3 ) - ( 5 1/3 - 6/5 ) - ( 6 - 7/4 + 3 /2 )
B = 1 / 3 - 3 / 4 - ( -3/ 5 ) + 1 /64 - 2 / 9 - 1 /36 + 1 / 15
C = 1 / 3 - 3 / 5 + 5/7 - 7/ 9 + 9 /11 - 11 / 13 + 13 / 15 + 11/ 13 - 9 /11 + 7 / 9
D = 1/99 - 1 /99 x 98 - 1 / 98 x 97 - 1 /97 x 96 - ........ - 1 / 3x 2 - 1/ 2 x 1
Tính giá trị biểu thức :
A = ( 3 - 1 / 4 + 2 /3 ) - ( 5 1/3 - 6/5 ) - ( 6 - 7/4 + 3 /2 )
B = 1 / 3 - 3 / 4 - ( -3/ 5 ) + 1 /64 - 2 / 9 - 1 /36 + 1 / 15
C = 1 / 3 - 3 / 5 + 5/7 - 7/ 9 + 9 /11 - 11 / 13 + 13 / 15 + 11/ 13 - 9 /11 + 7 / 9
D = 1/99 - 1 /99 x 98 - 1 / 98 x 97 - 1 /97 x 96 - ........ - 1 / 3x 2 - 1/ 2 x 1
Tính
A=(1/2-1/3)(1/2-1/5)(1/2-1/7)...(1/2-1/99)
Tính:
I=(\(\dfrac{1}{2}\)-\(\dfrac{1}{3}\)).(\(\dfrac{1}{2}\)-\(\dfrac{1}{5}\)).(\(\dfrac{1}{2}\)-\(\dfrac{1}{7}\)). ... .(\(\dfrac{1}{2}\)-\(\dfrac{1}{99}\))
1.a)(x+3/5).(x+1)<0
b)(x-1/3).(x+2/5)>0
2.B=(1-2/5).(1-2/7).(1-2/9).....(1-22/99)