thuc hien phep tinh(1/2+3/4+7/8+15/16+31/32+63/64) -5
ban nao lam duoc minh like cho>,<...........................!!!!!!!
Thuc hien phep tinh:
a) 32.(-1/2)3+1/4
b) 16.(1/2)2.1/2
c) 17/22+4/25+29/25+0,5+5/22
d) 3/11-7/15+8/11-8/15+0.25
Cac ban ghi cac buoc lam gjum mik nha
Thuc hien phep tinh:
a.3/7.11/15+3/7:15/14+2/7
b.(-7/15).5/8.15/-7(-32)
c.[(1/9:8/27):-1/3]:81/128
d.-66(1/2-1/3+1/11)+124(-37)+63(-124)
GIUP MINH NHA!
Chung minh rang:
1/2-1/4+1/8-1/16+1/32-1/64<1/3
BAN NAO NHANH TAY SE DUOC LIKE! chieu nay minh thi roi^-^
1/2 đấy
chúc bạn thi tốt nhé mk thitwf chiêu qua rùi!^_^
thuc hien phep tinh
a, 516x2,15
b, 2,1655 : 5
c, 15/4 x 8/3 x 16/25 x 1/5
d, 3/7 : 5/4 x 3/5
a, 516 x 2,15 = 1109,4
b, 2,1655 : 5 = 0,4331
c, \(\frac{15}{4}\)x \(\frac{8}{3}\)x \(\frac{16}{25}\)x \(\frac{1}{5}\)
= 10 x \(\frac{16}{25}x\frac{1}{5}\)
= \(\frac{32}{5}x\frac{1}{5}\)
= \(\frac{32}{25}\)
d, \(\frac{3}{7}:\frac{5}{4}x\frac{3}{5}\)
= \(\frac{3}{7}x\frac{4}{5}x\frac{3}{5}\)
= \(\frac{12}{35}x\frac{3}{5}\)
= \(\frac{36}{175}\)
a, 516x2,15=1109,4
b, 2,1655 : 5=0,4331
c, 15/4 x 8/3 x 16/25 x 1/5
=10x16/25 x 1/5
=6,4x1/5
=1.28
d, 3/7 : 5/4 x 3/5=12/35x3/5=36/175
Thuc hien phep tinh:
(163 - 642) :8
1) Thuc hien phep tinh:
a) 4^6 × 9^2 / 6^3 × 8^2
b) 5^6 × 15^4 /5^4 × 3^3
c) 3^9 - 2^3 × 3^7 + 2^10 × 3^2 - 2^13 / 3^10 - 2^2 × 3^7 + 2^10 × 3^3 - 2^12
d) (1/9)^10 : (1/3)^20
e) (1/64)^5 × (1/4)^7
2) Chung minh rang:
a)2014^100+2014^99 chia het cho 2015
b) 4^13+32^5-8^8 chia het cho 5
c) 81^27-27^9-9^13 chia het cho 405
Help me!! Pleass!!
Chung minh rang :
1/2-1/4+1/8-1/16+1/32-1/64 nho hon 1/3
Ban nao nhanh tay se nhan duoc LIKE!
Đặt \(A=\frac{1}{2}-\frac{1}{4}+\frac{1}{8}-\frac{1}{16}+\frac{1}{32}-\frac{1}{64}=\frac{1}{2}-\frac{1}{2^2}+\frac{1}{2^3}-\frac{1}{2^4}+\frac{1}{2^5}-\frac{1}{2^6}\)
\(2A=1-\frac{1}{2}+\frac{1}{2^2}-\frac{1}{2^3}+\frac{1}{2^4}-\frac{1}{2^5}\)
\(2A+A=3A=1-\frac{1}{2^6}=\frac{2^6-1}{2^6}< 1\)
\(\Rightarrow3A< 1\Rightarrow A< \frac{1}{3}\)(ĐPCM)
Thuc hien phep tinh sau:
( 163 - 642) :83
\(\left(16^3-64^2\right):8^3\)
\(\Leftrightarrow\left(4096-4096\right):512\)
\(\Leftrightarrow0.512\)
\(\Leftrightarrow0\)
Thuc hien phep tinh
A, 3/7 + 1/2 - (-3)/70
B, 3/5 + -1/25 - 35/100
C, 5/12 - 3/-16 + 3/4
D, 5/15 + 4/-12 + 1/7 - 1/-6
a,3/7 +1/2-[-3]/70
=13/14 -[-3]/70
=65/70 -[-3]/70
=34/35
b,3/5+-1/25 -35/100
=14/25 - 35/100
=56 /100 -35/100
= 21/100
c ,5/12 -3/-16+3/4
=29/48 +3/4
= 29/48 +36/48
=65/48
d, 5/15 +4/-12 +1/7 -1/-6
= 1/3 +1/-3 +1/7-1/-6
=0+1/7-1/-6
= 13/42
A.\(\dfrac{3}{7}+\dfrac{1}{2}+\dfrac{\left(-3\right)}{70}\)
=\([\dfrac{30}{70}+\dfrac{\left(-3\right)}{70}]\)+\(\dfrac{1}{2}\)
= \(\dfrac{27}{70}+\dfrac{35}{70}\)
=\(\dfrac{62}{70}=\dfrac{31}{35}\)
B.\(\dfrac{3}{5}+\dfrac{-1}{25}-\dfrac{35}{100}\)
=\(\dfrac{60}{100}+\dfrac{-4}{100}-\dfrac{35}{100}\)
=\(\dfrac{60+\left(-4\right)-35}{100}\)
=\(\dfrac{21}{100}\)
C.\(\dfrac{5}{12}-\dfrac{3}{-16}+\dfrac{3}{4}\)
=\(\left(\dfrac{5}{12}+\dfrac{9}{12}\right)-\dfrac{-3}{16}\)
=\(\dfrac{7}{6}-\dfrac{-3}{16}\)
=\(\dfrac{56}{48}-\dfrac{-9}{48}\)=\(\dfrac{65}{48}\)
D.\(\dfrac{5}{15}+\dfrac{4}{-12}+\dfrac{1}{7}-\dfrac{1}{-6}\)
=\(\dfrac{1}{3}+\dfrac{1}{7}+(\dfrac{-2}{6}-\dfrac{-1}{6})\)
=\(\dfrac{1}{3}+\dfrac{1}{7}+\dfrac{-1}{6}\)
=\((\dfrac{1}{3}+\dfrac{-1}{6})+\dfrac{1}{7}\)
=\(\dfrac{1}{6}+\dfrac{1}{7}\)=\(\dfrac{13}{42}\)