a) 231 + (-54) + (-231) + (-64) + 123 + 277
b) 1 + 3 + (-5) + (-7) + 9 + 11 +...+ 97 + 99
c) 1 + (-2) + (-3) + 4 + 5 + (-6) + (-7) + 8 + 9 +...+ (-2015) + (-2016)
1^2+3^4+5^6+7^8+9^10=?
123+132+231+213+321+312=?
1.200.400.0=?
Tinh hop li:
a) 28 .( 231 + 69 ) + 72 . ( 231 + 69 )
b) 1 + 2 - 3 - 4 + 5 + 6 -7 -8 + ..... 299 - 300 + 301 + 302
c) 1 + 2 + 22 + 23 + 24 + ..... + 299 + 2100
d) 5 + 53 + 55 + ..... + 597 + 599
Nho cac ban giai gium !!!
Tính
1) 12.2.25+29.25+59.25
2) 25.(231+69)+72.(231+69)
3) 39.(250+87)+64.(240+97)
4) 36.28+36.82+64.69+64.41
tính nhanh
1) 12.2.25+29.25+59.25
2) 25.(231+69)+72.(231+69)
3) 39.(250+87)+64.(240+97)
4) 36.28+36.82+64.69+64.41
123-5.(x+4)=38
10+2x=2.(32-1)
2.x-138=23.32
[102+(28-2x)]:20-5=1
231-(x-6)=1339:13
tính hợp lí
a) 28x(231+69)+72x(231+69)
b) 10x46x95+69x120/84:312-611
c)1+2+22+2324+.....+2100
d)5+53+55+.....+597+599
100 + 20 : 99 + 123 - 893+9090+(-98+-90)-99+1+2+98:3\4:98\2
(dùng máy tính nha)
Tính nhanh:
a) \(2.\dfrac{3}{7}+\left(\dfrac{2}{9}-1\dfrac{3}{7}\right)-\dfrac{5}{3}:\dfrac{1}{9}\)
b) \(\dfrac{-11}{23}.\dfrac{6}{7}+\dfrac{8}{7}.\dfrac{-11}{23}-\dfrac{1}{23}\)
c) \(\left(\dfrac{377}{-231}-\dfrac{123}{89}+\dfrac{34}{791}\right).\left(\dfrac{1}{6}-\dfrac{1}{8}-\dfrac{1}{24}\right)\)
d) \(19\dfrac{5}{8}:\dfrac{7}{12}-15\dfrac{1}{4}:\dfrac{7}{12}\)
e) \(\dfrac{2}{5}.\dfrac{1}{3}-\dfrac{2}{15}:\dfrac{1}{5}+\dfrac{3}{5}.\dfrac{1}{3}\)