1. Tính hợp lí : A. (0.25)^3×32
B. (-0.125)^3.80^4
C. 8^2×4^5/2^20
D. 81^11×3^17/27^10×9^15
bài 1; tính hợp lí
a/ (0,25)^3 . 32
b/ (-o,125)^3.80^4
c/ 8^2.4^5
2^20
d/ 81^11.3^17
27^10.9^15
a) =\(\left(\frac{1}{4}\right)^3\cdot2^5=\frac{1}{2^6}2^5=0,5\)
b) \(=\left(\frac{1}{8}\right)^3\cdot8^4\cdot10^4=80.000\)
c) \(=8^2\cdot\frac{4^5}{2^{20}}=\frac{2^6\cdot2^{10}}{2^{20}}=\frac{1}{2^4}=0,0625\)
d) = \(\frac{81^{11}\cdot3^{17}}{27^{10}\cdot9^{15}}=\frac{3^{44}\cdot3^{17}}{3^{30}\cdot3^{30}}=\frac{3^{61}}{3^{60}}=3\)
bai 1:tinh
a,(0.25)3.32
b,85.45/220
c,8111.317/2710.915
bài 1 : tính hợp lí
a) \( \left(-0,125\right)^3.80^4\)
b) \(\frac{81^{11}.3^{17}}{27^{10}.9^{15}}\)
bài 2 : rút gọn
a) \(A=\frac{16^3.3^{10}+120.6^9}{4^6.3^{12}+6^{11}}\)
b)\(B=\left(6^9.2^{10}+12^{10}\right):\left(2^{19}.27^3+15.4^9.9^4\right)\)
c)\(H=x+\frac{0,2-0,375+\frac{5}{11}}{-0,3+\frac{9}{16}-\frac{15}{22}}vs,x=-\frac{1}{3}\)
Tính:
a) \(\left(-0,125\right)^3.80^4\)
b) \(\frac{81^{11}.3^{17}}{27^{10}.9^{15}}\)
a/ \(\left(-0,125\right)^3:80^4=-\frac{1}{512}.80^4=-80000\)
b/ \(\frac{81^{11}.3^{17}}{27^{10}.9^{15}}=3\)
a, ( - 0, 125)^3 . 80^ 4
\(\left(-\frac{1}{8}\right)^3.80^4=\frac{-1^3}{8^3}\cdot8^4\cdot10^4\) = \(-8\cdot10^4=-8.1000=-8000\)
b,\(\frac{81^{11}.3^{17}}{27^{10}.9^{15}}=\frac{3^{4.11}.3^{17}}{3^{3.10}.3^{2.15}}=\frac{3^{44}.3^{17}}{3^{30}.3^{30}}=\frac{3^{44+17}}{3^{30+30}}=\frac{3^{61}}{3^{60}}=3\)
Tính hợp lí
a/(0,25)3 .32
b/ (-0,125)3 .804
c/ \(\frac{8^2.4^5}{2^{20}}\)
d/ \(\frac{81^{11}.3^{17}}{27^{10}.9^{15}}\)
1.Tìm các số nguyên x:
5/17+-4/9+-20/31+12/17+-11/31<x<=-3/7+7/15+4/-7+8/15+2/3
2. Tính
A=5-10/19+15/143-5/81+8-16/26+24/243-8/181
6-12/19+18/143-6/81+9-18/26+27/243-9/181
Tính hợp lý
a) (0,25)3.32
b) (-0,125)3.804
c) 82.45/220
d) 8111.317/2710.915
a) (0.25)^3*32
= (0.5)^5*0.5*2^5
=1^5*0.5
=1*0.5
=0.5
b)(-0.125)^3*80^4
=(-0.125)^3*80^3*80
=(-0.125*80)^3*80
=(-10)^3
=-1000*80
=-80000
c) 8^2*4^5/2^20
=(23)2*(22)5*2^20
=2^6*2^10*2^20
=2^36
d)81^11*3^17/27^10*9^15
=((34)11*3^17)/(33)10*(32)15
=(3^44*3^17)/(3^30*3^30)
=3^61/3^60
=3
Bài b) dòng thứ 3 từ dưới đếm lên, phải là, (-10)^3*80 nha, gấp quá mình ghi nhầm ;)
81^11*3^17/27^10*9^15
=( 3^4 )^11 * 3^17 / ( 3^3 )^10 * ( 3^2 )^15
=3^44 * 3^17 / 3^30 * 3^30
=3^61 / 3^60
=3
Câu 1 : thực hiện phép tính ( tính hợp lí nếu có thể ) A, 3/5 + -4/9 B, 3/5 + 2/5 . 15/8 C, 7/2 . 8/13 + 8/13 . -5/2 + 8/13 D, -5/17 . -9/23 + 9/23 . -22/17 + 11 9/23 Lưu ý : 11 9/23 là hỗn số
`a)3/5+(-4/9)`
`=3/5-4/9`
`=27/45-20/45`
`=7/45`
`b)3/5+2/5 . 15/8`
`=3/5 + 30/40`
`=3/5+3/4`
`=12/20+15/20`
`=27/20`
`c)7/2 . 8/13 + 8/13 . (-5/2)`
`=8/13 . (7/2 +(-5)/2)`
`=8/13 . 1`
`=8/13`
`d)-5/17 . (-9/23)+9/23 . (-22/17) + 11 9/23`
`=-5/17 . (-9/23) + 9/23 . (-1) . 22/17 + 11 + 9/23`
`=-5/17 . (-9/23) + (-9/23) . 22/17+11+9/23`
`= -9/23 ( -5/17 + 22/17)+11+9/23`
`= - 9/23 . 1+11+9/23`
`=-9/23+11+9/23`
`=(-9/23+9/23)+11`
`=0+11`
`=11`
a: =27/45-20/45=7/45
b: =3/5+30/40
=3/5+3/4
=12/20+15/20
=27/20
c: =8/13(7/2-5/2+1)=8/13*2=16/13
d: =9/23*5/17-9/23*22/17+11+9/23
=-9/23+11+9/23
=11
a) -5/11 + ( -6/11 + 1 )
b) -13/17 + ( 13/-21 + -4/17 )
c) -5/12 . 7/-17 . 9/-20
d) 13/17 . 4/-5 + 13/17 . -3/4
e) -5/7 . 2/11 + -5/7 . 9/11 + 5/7
f) -2/5 . (-6) + 3/4 . 4/-10
a: =-5/11-6/11+1=-11/11+1=0
b: =-13/17-13/21-4/17=-1-13/21=-34/21
b: \(=-\dfrac{5}{12}\cdot\dfrac{9}{20}\cdot\dfrac{7}{17}=\dfrac{-21}{272}\)
d: \(=\dfrac{13}{17}\left(-\dfrac{4}{5}-\dfrac{3}{4}\right)=\dfrac{13}{17}\cdot\dfrac{-31}{20}=\dfrac{-403}{340}\)