Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a: 3,26-1,549=1,711
b: 0,167-2,396=-2,229
c: -3,29-0,867=-4,157
d: -6,09-3,65=-9,74
e: \(\left(-2.5\right)\cdot\left(-4\right)=2.5\cdot4=10\)
f: \(=\left[\left(-2.5\right)\cdot\left(-4\right)\right]\cdot\left(-7\right)=-7\cdot10=-70\)
a: 3,26-1,549=1,711
b: 0,167-2,396=-2,229
c: -3,29-0,867=-4,157
d: -6,09-3,65=-9,74
e: \(\left(-2.5\right)\cdot\left(-4\right)=2.5\cdot4=10\)
f: \(=\left[\left(-2.5\right)\cdot\left(-4\right)\right]\cdot\left(-7\right)=-7\cdot10=-70\)
1a, (-3,8) + [ (-5,7)+3,8]
= (-3,8+3,8) -5,7
= -5,7
b, 31,4 +[6,4 +(-18)]
= 31,4 - 11,6
= 19,8
c,[(9,6 )+4,5 ] +[9,6 +(-1,5)]
= 9,6 +9,6 +(4,5-1,5)
= 19,2 +3
=22,2
d, [ (-4,9) + (-7,8)] +[1,9+2,8]
= (-4,9 +1,9)+ (-7,8+2,8)
= -3 -5
=-8
e, (3,1-2,5)-(-2,5+3,1)
= (3,1-3,1)+(2,5-2,5)
=0
f, (5,3 -2,8 )- (4+5,3)
= (5,3-5,3) -2,8-4
= -6,8
g, -(251,3 +281 )+ 3,251 -(1-281)
= -251,3-281+3,251 -1+281
= (-281+281) -251,3 +3,251 -1
= -249,049
h,-(3/54+3/4)-(-3/4 +2/5)
= -3/54-3/4 +3/4 +2/5
=(-3/4+3/4) -3/54 +2/5
=123/270
chúc bạn học tốt
\(A=\left(3,1-2,5\right)-\left(-2,5+3,1\right)\)
\(A=3,1-2,5+2,5-3,1\)
\(A=\left(3,1-3,1\right)-\left(2,5-2,5\right)\)
\(A=0-0\)
\(A=0\)
\(B=\left(5,3-2,8\right)-\left(4+5,3\right)\)
\(B=5,3-2,8-4-5,3\)
\(B=\left(5,3-5,3\right)-\left(2,8+4\right)\\ B=0-6,8\\ B=-6,8\)
\(A=\left(3,1-2,5\right)-\left(-2,5+3,1\right)\)
\(=3,1-2,5+2,5-3,1=0\)
\(B=\left(5,3-2,8\right)-\left(4+5,3\right)\)
\(=5,3-2,8-4-5,3=-6,8\)
\(C=-\left(251.3+281\right)+3.215-\left(1-281\right)\)
\(=-753-281+645-1+281\)
\(=-753+654-1=-100\)
\(D=-\left(\dfrac{3}{5}+\dfrac{3}{4}\right)-\left(\dfrac{-3}{4}+\dfrac{2}{5}\right)\)
\(=-\dfrac{3}{5}-\dfrac{3}{4}+\dfrac{3}{4}-\dfrac{2}{5}=\dfrac{-3}{5}-\dfrac{2}{5}=-1\)
\(A=\left(3,1-2,5\right)-\left(-2,5+3,1\right)\)
\(=3,1-2,5+2,5-3,1\)
\(=\left(3,1-3,1\right)-\left(2,5-2,5\right)\)
\(=0\)
Vậy \(A=0.\)
\(B=\left(5,3-2,8\right)-\left(4+5,3\right)\)
\(=5,3-2,8-4-5,3\)
\(=\left(5,3-5,3\right)-\left(2,8+4\right)\)
\(=-\dfrac{34}{5}\)
Vậy \(B=\dfrac{-34}{5}.\)
\(C=-\left(251.3+281\right)+3.215-\left(1-281\right)\)
\(=-251.3-281+3.215-1+281\)
\(=-753-\left(281-281\right)+645\)
\(=-753+645=-108\)
Vậy \(C=-108.\)
\(D=-\left(\dfrac{3}{5}+\dfrac{3}{4}\right)-\left(-\dfrac{3}{4}+\dfrac{2}{5}\right)\)
\(=-\dfrac{3}{5}-\dfrac{3}{4}+\dfrac{3}{4}-\dfrac{2}{5}\)
\(=\left(\dfrac{-3}{5}-\dfrac{2}{5}\right)-\left(\dfrac{3}{4}-\dfrac{3}{4}\right)\)
\(=-1\)
Vậy D = -1.
a: \(=\left(\dfrac{11}{17}+\dfrac{6}{17}\right)+\left(-\dfrac{5}{13}-\dfrac{8}{13}\right)+\dfrac{11}{25}\)
=11/25+1-1=11/25
b: \(=\sqrt{36\cdot\dfrac{1}{4}}+11=9+11=20\)
c: \(=\left(0.25\right)^8\cdot4^8=\left(0.25\cdot4\right)^8=1\)
d: \(=2.8\left(-6.5-3.5\right)=-10\cdot2.8=-28\)
a) \(\dfrac{1,2}{x+3}=\dfrac{5}{4}\)
\(\Rightarrow\left(x+3\right).5=1,2.4\)
\(\Rightarrow\left(x+3\right).5=4,8\)
\(\Rightarrow x+3=4,8:5\)
\(\Rightarrow x+3=0,96\)
\(\Rightarrow x=-2,04\)
vậy \(x=-2,04\)
b)\(\dfrac{3}{5}:\dfrac{2x}{15}=\dfrac{1}{2}:\dfrac{4}{5}\)
\(\Rightarrow\dfrac{3}{5}:\dfrac{2x}{15}=\dfrac{5}{8}\)
\(\Rightarrow\dfrac{2x}{15}=\dfrac{3}{5}:\dfrac{5}{8}\)
\(\Rightarrow\dfrac{2x}{15}=\dfrac{24}{25}\)
\(\Rightarrow15.24=\left(2x\right).25\)
\(\Rightarrow360=\left(2x\right).25\)
\(\Rightarrow360:25=2x\)
\(\Rightarrow14,4=2x\)
\(\Rightarrow x=7,2\)
vậy \(x=7,2\)
\(a,\dfrac{1,2}{x+3}=\dfrac{5}{4}\\ \left(x+3\right).5=1,2.4\\ 5x+8=4,8\\ 5x=4,8-8\\ 5x=-3,2\\ x=-3,2:5=-0,64\)
\(b,\dfrac{3}{5}:\dfrac{2x}{15}=\dfrac{1}{2}:\dfrac{4}{5}\\ \dfrac{2x}{15}=\dfrac{3}{5}\cdot\dfrac{4}{5}:\dfrac{1}{2}\\ \dfrac{2x}{15}=\dfrac{12}{25}.2\\ \dfrac{2x}{25}=\dfrac{24}{25}\\ 2x=\dfrac{24}{25}.5\\ 2x=\dfrac{24}{5}\\ x=\dfrac{24}{5}\cdot\dfrac{1}{2}=\dfrac{12}{5}\)
\(c,-\dfrac{4}{2,5}:3,5=1,5:x\\ x=3,5.1,5:\left(-\dfrac{4}{25}\right)\\ x=\dfrac{21}{4}\cdot\left(-\dfrac{25}{4}\right)=-\dfrac{525}{16}\)
\(d,0,12:3=2x:\dfrac{3}{5}\\ 2x=0,12\cdot\dfrac{3}{5}:3\\ 2x=\dfrac{9}{125}\cdot\dfrac{1}{3}\\ 2x=\dfrac{3}{125}\\ x=\dfrac{3}{125}\cdot\dfrac{1}{2}=\dfrac{3}{250}\)
\(A=4,8.\left(3,1-1,5\right)+1,5.\left(4,8-3,1\right)\)
\(A=4,8.3,1-4,8.1,5+1,5.4,8-1,5.3,1\)
\(A=3,1.\left(4,8-1,5\right)-4,8\left(1,5+1,5\right)\)
\(A=3,1.3,3-4,8.3\)
\(A=10,23-14,4=-4,17\)
\(B=\dfrac{2^{19}.27^3+15.4^9.9^4}{6^9.2^{10}+12^{10}}=\dfrac{2^{19}.\left(3^3\right)^3+3.5.\left(2^2\right)^9.\left(3^2\right)^4}{\left(2.3\right)^9.2^{10}+\left(3.2^2\right)^{10}}=\dfrac{2^{19}.3^9+3.5.2^{18}.3^8}{2.3^9.2^{10}+3^{10}.\left(2^2\right)^{10}}=\dfrac{2^{19}.3^9+3^9.2^{18}.5}{2^{11}.3^9+3^{10}.2^{20}}=\dfrac{2^{18}.3^9\left(2+5\right)}{2^{11}.3^9\left(1+3.2^9\right)}=\dfrac{2^7.7}{1+3.2^9}\)
Bài 5 :
a, ( -4,8 ) + \(\left[\left(-5,7\right)+\left(4,8\right)\right]\)
= (-4,8) + ( 4,8 ) + ( -5,7 )
= (-5,7 )
b) [(-9,6) + (+1,5)] + [(+9,6) + (-1,5)]
= (-9,6 ) + 9,6 + 1,5 + ( -1,5 )
= 0
c) (3,1 - 2,5) - (-2,5 + 3,1)
= 3,1 - 2,5 + 2,5 - 3,1
= 3,1 -3,1 -2,5 + 2,5
=0
= 3,1 - 2,5 + 2,5 + 3,1
= ( 3,1 - 3,1 ) + ( -2,5 - 2,5 )
= 0
d) 2,7 - (-4,3) + (-8,5) - (-0,6)
= 2,7 + 4,3 - 7 ,9
= 7 - 7,9
= -0,9
d) 2,7 - (-4,3) + (-8,5) - (-0,6)
= 2,7 + 4,3 + 8,5 + 0,6
= 7 + 9,1
= 16,1
e, - \(\left(\dfrac{3}{5}+\dfrac{3}{4}\right)-\left(\dfrac{3}{4}+\dfrac{2}{5}\right)\)
= \(\dfrac{-3}{5}+\dfrac{3}{4}-\dfrac{3}{4}-\dfrac{2}{5}\)
= \(\dfrac{-3}{5}-\dfrac{2}{5}+\dfrac{3}{4}-\dfrac{3}{4}\)
= -1
f) [(-4,9) + (-37,8)] + [(+1,9) + (+2,8)]
= - 4,9 - 37,8 + 1,9 + 2,8
= ( -4,9 + 1,9 ) + ( -37,8 + 2,8 )
= -3 + (-35)
= -38
g) (-4,1) + (-13,7) + (+31) + (-5,9) + (-6,3)
= (-4,1) + ( -5,9 ) + ( -13,7 ) + ( -6,3) + 31
= - 10 - 20 + 31
= 1
h) (-6,5) . 2,8 + 2,8 . (-3,5)
= 2,8 . [ -6,5 - 3,5 ]
= 2,8 . (-10 )
= - 28