8 + 67 = ?
tính nhanh:
a)(-119). (-125). 4. (-8). (-25)
b)(-67). (-1)mũ 200. (-8). 125. (-1)mũ 2n+1
c)-67. 52- 48. 67
d)42.(-119)+ 119. (-58)
a) (-119).(-125).4.(-8).(-25) = [(-125).(-8)].[(-25).(-4)].(-119) = 1000.100.(-119) = 100000.(-119) = -11900000
b) (-67).(-1)^200.(-8).125.(-1)^2n+1 = -67.1.[(-8).125].(-1) = -67.(-1000).(-1) = 67000 . (-1) = -67000
c) -67.52-48.67 = 67.(-52)-48.67 = 67. (-52-48) = 67.(-100) = -6700
d)42.(-119)+119.(-58) = -42.119+119.(-58)=119.[-42+(-58)] = 119.(-100)=-11900
(-57).(67-34)-67.(34-57)
(-4).(+125).(-25).(-6).(-8)
54 : 67 - 8/8 =.....
tính bằng cách thuận tiện nhất :
4 x 26 x 25 63 x 78 - 53 x 78
67 x 92 + 67 x 8 8 x 23 x 25 x 125
a: =100x26=2600
b: =78x10=780
c: =67x100=6700
d: =1000x575=575000
\(4\times26\times25=\left(4\times25\right)\times26=100\times26=2600\\ 63\times78-53\times78=\left(63-53\right)\times78=10\times78=780\\ 67\times92+67\times8=67\times\left(92+8\right)=67\times100=6700\\ 8\times23\times25\times125=\left(8\times125\right)\times\left(23\times25\right)=1000\times575=57500\)
a: =100x26=2600
b: =78x10=780
c: =67x100=6700
d: =1000x575=575000
Tính nhanh
a) 31/23 - (7/32 + 8/23)
b) 38/45 - (8/45 - 17/51 - 3/11)
c)(1/3 + 12/67 + 13/41) - ( 79/67 - 28/41)
d) 1/5 + -1/6 + 1/7 + -1/8 + 1/9 + 1/8 + -1/7 + 1/6 + -1/5
Tính nhanh
a) 31/23 - (7/32 + 8/23)
b) 38/45 - (8/45 - 17/51 - 3/11)
c)(1/3 + 12/67 + 13/41) - ( 79/67 - 28/41)
d) 1/5 + -1/6 + 1/7 + -1/8 + 1/9 + 1/8 + -1/7 + 1/6 + -1/5
`a,`
`31/23-(7/32+8/23)`
`=31/23-7/32-8/23`
`=(31/23-8/23)-7/32`
`=1-7/32=25/32`
`b,`
`38/45-(8/45-17/51-3/11)`
`=38/45-8/45+17/51+3/11`
`= (38/45-8/45)+17/51+3/11`
`=2/3+17/51+3/11`
`=1+3/11=14/11`
`c,`
`(1/3+12/67+13/41)-(79/67-28/41)`
`= 1/3+12/67+13/41-79/67+28/41`
`= 1/3+(12/67-79/67)+(13/41+28/41)`
`= 1/3+(-1)+1=1/3+(-1+1)=1/3+0=1/3`
`d,`
`1/5+(-1/6)+1/7+(-1/8)+1/9+1/8+(-1/7)+1/6+(-1/5)`
`= (1/5+ -1/5)+(-1/6+1/6)+(1/7+ -1/7)+(-1/8 +1/8)+1/9`
`= 0+0+0+0+1/9=1/9 .`
Tính nhanh :
a, (-67).(1- 301) - 301 . 67
b, (-4).(+4).(-125).(+25).(-8)
Tinh nhanh
a)(-4).(+125).(-25).(-6).(-8)
b)(-57).(67-34)-67.(34-57)
Ý là sao ???????????????????????????????????????????????????
a) (-4)(125)(-25)(-6)(-8)
=[(-4)(-25)].[125.(-8)].(-6)
= 100 . (-1000) . (-6)
= -100000.(-6)=600000
b)(-2)(-2)(-2)(-3)(-3)(-3)
= (-2)3.(-3)3
= [(-2)(-3)]3 = 63 = 216
a) (-4).125.(-25).(-6).(-8)
=[(-4).(-25)].[-8.125].-6
=100.-1000.-6
=600000
b)=63=216
tính nhanh
a, ( -4 ) . ( +3 ) . ( -125 ) . ( +25 ) . ( -8 )
b, ( -67 ) . ( 1 - 301 ) - 301 . 67
( -4 ) . 3 . ( -125 ) . 25 . ( -8 )
= [ -4 . 25 ] . [ -125 . ( -8 ) ] . 3
= -100 . 1000 . 3
= -100 000 . 3
= -300 000
( -67 ) . ( 1 - 301 ) - 301 . 67
= ( -67 ) . 1 - 301 - 301 . 67
= -67 . 1
= -67
a, ( -4 ) . ( +3 ) . ( -125 ) . ( +25 ) . ( -8 )
= ( - 4 ) . ( + 25 ) . ( - 125 ) . ( - 8 ) . ( + 3 )
= 100 . 1000 . 3
= 100000 . 3
= 300000
b, ( -67 ) . ( 1 - 301 ) - 301 . 67
= ( - 67 ) . 1 + 67 . 301 - 301 . 67
= -67 . 1
= - 67
a, ( -4 ) . ( +3 ) . ( -125 ) . ( +25 ) . ( -8 )
=>300000
b, ( -67 ) . ( 1 - 301 ) - 301 . 67
=>-67
1+1+6+7+5+8+5+8+9+6+8+9+9+67=?