a,87.36 + 87.64 = 87 . (64 + 36) = 87 x 100 = 8700
b, 91.51 + 49.163 - 49.72 = 91.51 + ( 49.163 - 49.72 ) = 91.51 + 49.91 = 91.(51+49) = 91.100 = 9100
Tìm x
(5x+1)^2n=36/49
(8x-1)^2n+1=5^2n+1
a,87.36 + 87.64 = 87 . (64 + 36) = 87 x 100 = 8700
b, 91.51 + 49.163 - 49.72 = 91.51 + ( 49.163 - 49.72 ) = 91.51 + 49.91 = 91.(51+49) = 91.100 = 9100
Tìm x
(5x+1)^2n=36/49
(8x-1)^2n+1=5^2n+1
tính thuận tiện
91.51+59.163-49.72
Tinh nhanh
A) 46+17+54
B) 4.37.25
C) 87.36+87.64
hay tinh phep tinh sau hop ly:
(13-135+49)-(13+49)
26.(24-11)-24.(26-11)
tinh hop li:
12-12+11+10-9+8-7+5-4+3+2-1
tim so nguyen x :
3x+27=9
2x+12=3(x-7)
2x^2-1=49
-|9-x|-5=12
cho:A=(-a-b+c)-(-a-b-c)
a)rut gon A
b)tinh gia tri cua A khi a=1;b= -1;c= -2
tinh hop li
A= 11 + 12 + ... + 40 + 41
tinh hop li:
a=(9765+3567)-(1467+8665)
ket hop phep cong a ] 997+37; b] 49+194; ket hop phep nhan a] 17.14 ; b] 25.28 ; tinh chat phan phoi phep nhan va phep cong a] 13.12 ; b] 53.11 ; c] 39.101 ;
997+37 49+194 tinh nhanh bang tinh chat ket hop cua phep cong