thuc hien phep tinh:
(1+2/3).(1+2/5).(1+2/7).....(1+2/2015)
nhanh dùm mình với, mai học rồi!!!!!
thuc hien phep tinh (Tinh nhanh neu co the)
(-5/12+7/4-3/8)-|4 va 1/2 -7 va 1/2|-( 1/4-5/2)
Thuc hien phep tinh :1 + 5 + 52 + 53 + 54 + ....+ 52015
1 + 5 + 52 + 53 + 54 + ....+ 52015
Đặt A= 1 + 5 + 52 + 53 + 54 + ....+ 52015
5A= 5 ( 1 + 5 + 52 + 53 + 54 + ....+ 52015)
5A= 5 + 52 + 53 + 54 + ....+ 52015+52016
5A- A= ( 5 + 52 + 53 + 54 + ....+ 52015+52016) -( 1 + 5 + 52 + 53 + 54 + ....+ 52015)
4A= 52016-1
A= (52016-1) :4
Vậy...
1) thuc hien phep tinh sau:
a)B=\(\left(\dfrac{5}{7}.0,6:3\dfrac{1}{2}\right)\) .(40%-1,4).(-2)^3
B = ( \(\dfrac{5}{7}.0,6:3\dfrac{1}{2}\)) . ( 40% - 1,4) . \(\left(-2\right)^3\)
= (\(\dfrac{5}{7}.\dfrac{3}{5}\): \(\dfrac{7}{2}\)) . ( \(\dfrac{2}{5}-\dfrac{7}{5}\)) . (-8)
= (\(\dfrac{15}{35}:\dfrac{7}{2}\)) . \(\dfrac{-5}{5}\) . ( -8)
= (\(\dfrac{3}{7}.\dfrac{2}{7}\)) . (-1) . (-8)
= \(\dfrac{6}{49}\) . (-1) . (-8)
= \(\dfrac{-6}{49}\) . (-8)
= \(\dfrac{48}{49}\)
Vậy: B =\(\dfrac{48}{49}\)
Nhớ tick nha
B=(\(\dfrac{3}{7}.\dfrac{2}{7}\)).(\(\dfrac{4}{10}-\dfrac{14}{10}\)).(-8)
B=\(\dfrac{3}{7}.\left(-1\right)\left(-8\right)\)
B=\(\dfrac{24}{7}\)
thuc hien cac phep tinh
1-2-3+4+5-6-7+...+2001-2002-2003+2004
thuc hien phep tinh (1-1/(1+2)).(1-1/(1+2+3))...(1-1/(1+2+3+...+2006))
thuc hien phep tinh
\(\frac{6}{7}+\frac{1}{7}.\frac{2}{7}+\frac{1}{7}.\frac{5}{7}\)
\(\frac{6}{7}+\frac{1}{7}.\frac{2}{7}+\frac{1}{7}.\frac{5}{7}=\frac{6}{7}+\frac{2}{14}+\frac{5}{14}=\frac{12}{14}+\frac{7}{14}=\frac{19}{14}\)
Tính nhanh : B = 1 + 2 + ( -3 ) + ( -4 ) + 5 + 6 + ( -7 ) + ( -8 ) +... + 2013 + 2014 + ( -2015 ) + ( -2016 ) ( Giúp mình nhanh với , mai phải đi học rồi :'( )
thuc hien phep tinh
a)(-3/7)^21 : (9/49)^6
b)3-(-67)^0+(1/2)^2 :2
Bai 1 : Thuc hien phep tinh :
a ) 295 - ( 31 - 2 ^2 . 5 ) ^ 2
b ) 7^9 : 7^7 - 3^2 + 2^3 .5^2
c ) 1200 : 2 + 6 ^2 . 2^1 +18
d )151 - 2^91 : 2 ^88 + 1^2 . 3
e ) 2 ^38 : 2 ^36 + 5^1 : 3^2 - 7 ^ 2
a) 295 - (31 - 22 x 5)2
= 295 - (31 - 4 x 5)2
= 295 - (31 - 20)2
= 295 - 112
= 295 - 121
= 174
b) 79 : 77 - 32 + 23 x 52
= 72 - 9 - 8 x 25
= 49 - 9 - 8 x 25
= 40 - 200
= -160
c) 1200 : 2 + 62 x 21 + 18
= 600 + 36 x 2 + 18
= 600 + 72 + 18
= 600 + 90
= 690
d) 151 - 291 : 288 + 12 x 3
= 151 - 23 + 1 x 3
= 151 - 8 + 1 x 3
= 151 - 8 + 3
= 151 - 11
= 140
e) 238 : 236 + 51 : 32 - 72
= 22 + 5 : 9 - 49
= 4 + 5 : 9 - 49
= 9 : 9 - 49
= 1 - 49
= -48
Học tốt!!!