a) (31/20 - 26/45) . -36<x<(51/56+8/21+1/3)-8/13.
b)(2/11.13 + 2/13.15 + 2/15.17+...+2/53.55)- x + 22/2 - 1/31=4/3.
c)(x+5).(3x-12)>0
giúp mình vs nhé tick
(31/20-26/45)-36/35<x<(51/56+8/321+1/3).8/13
(31\20*26\45)*-36\35<x<(51\56+8\21+1\3)*8\13
Tìm số nguyên x, biết: ( \(\dfrac{31}{20}-\dfrac{26}{45}\) ) . \(\dfrac{-36}{35}< x< \left(\dfrac{51}{56}+\dfrac{8}{21}+\dfrac{1}{3}\right).\dfrac{8}{13}\)
=\(\dfrac{35}{36}.\dfrac{-36}{35}< x< \dfrac{13}{8}.\dfrac{8}{13}\)
= -1 < x < 1
vậy x = 0
Tính: a, ( 51/56 + 8/21 + 16/48).32/65
b, ( 31/20 - 26/45).36/49
c, 5/39.(39/5.5/3+ 26/3.39/5)
Các bạn giúp mình giải bài toán này nha, tớ cảm ơn các bạn
Tìm số nguyên x biết:
-36/35.(31/20-26/45)< x<(51/56+8/21+1/3).8/13
Trình bày rõ ra luôn nha.Cảm ơn
Bài 1 : Tính nhanh
a) (-48)-72+36*(40-404)
b) 25*(-23)+47*(-35)-20*(-35)
c) 29*(67)-45*67+26*(67)
d) 4*(-5)-125*(-2)mũ 3+(-10) mũ 3*(-2)
Bài 2: Tính nhanh
a) (26-6)*(-4)+31*(-7-13)
b) (47-17)*(-5)+22*(-13-17)
c) (35-85)*11+29*(-14-36)
d) (153-53)*(-37)+37*(-42-58)
Giúp mình với nhé
a) (26-6)*(-4)+31*(-7-13)
=-80+-620
=-700
hacker 2k6
a = 5/11*16 + 5 / 16 *21 + 5/ 21*26 + 5/ 26 *31 +5/ 31*36 + 5/ 36 *41
\(\frac{5}{11.16}+\frac{5}{16.21}+..+\frac{5}{36.41}\)
\(=\frac{1}{11}-\frac{1}{16}+\frac{1}{16}-\frac{1}{21}+..+\frac{1}{36}-\frac{1}{41}\)
\(=\frac{1}{11}-\frac{1}{41}\)
= bn tự timnhs nha......................................
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
\(\frac{5}{11.16}+\frac{5}{16.21}+...+\frac{5}{36.41}\)
\(=\frac{1}{11}-\frac{1}{16}+\frac{1}{16}-\frac{1}{21}+...+\frac{1}{36}-\frac{1}{41}\)
\(=\frac{1}{11}-\frac{1}{41}\)
\(=\frac{30}{451}\)
_Chúc bạn học tốt_
\(A=\frac{5}{11\times16}+\frac{5}{16\times21}+....+\frac{5}{36\times41}.\)
\(A=\frac{1}{11}-\frac{1}{16}+\frac{1}{16}-\frac{1}{21}+...+\frac{1}{36}-\frac{1}{41}\)
\(A=\frac{1}{11}-\frac{4}{41}=\frac{30}{451}\)
A=55/11*16+55/16*21+55/21*26+55/26*31+55/31*36+55/36*41
A=55/11.16+55/16.21+...+55/36.41
A=11x(1/11−1/16+1/16−1/21+...+1/36−1/41)
A=11x(1/11−1/41)
A=11x30/451
A=30/41
tính : A=55/11*16 + 55/16*21 + 55/21*26 + 55/26*31 + 55/31*36 + 55/36*41
A=55*[(1/11*16) * 1/5 + (1/16*21) * 1/5 + (1/21*26) * 1/5 + (1/26*31) * 1/5 + (1/31*36) * 1/5 + (1/36*41) * 1/5 ]
= 55* [ (1/11*16) + (1/16*21) + (1/21*26) + (1/26*31) + (1/31*36) + (1/36*41) ] * 1/5
= 55 * [ 1/11-1/16+1/16-1/21+1/21-1/26+1/26-1/31+1/31-1/36+1/36-1/41) * 1/5
= 55 * ( 1/11 - 1/41 ) * 1/5
= 30/41