\(\dfrac{5}{13}.\dfrac{8}{15}+\dfrac{5}{13}.\dfrac{26}{15}-\dfrac{5}{13}.\dfrac{8}{15}.\\ =\dfrac{5}{13}.\left(\dfrac{8}{15}+\dfrac{26}{15}-\dfrac{8}{15}\right).\\ =\dfrac{5}{13}.\dfrac{26}{15}=\dfrac{2}{3}.\)

\(\dfrac{5}{13}\times\dfrac{8}{15}+\dfrac{5}{13}\times\dfrac{26}{15}-\dfrac{5}{13}\times\dfrac{8}{15}\)

\(=\dfrac{5}{13}\times\left(\dfrac{8}{15}+\dfrac{26}{15}-\dfrac{8}{15}\right)\)

\(=\dfrac{5}{13}\times\dfrac{26}{15}\)

\(\dfrac{2}{3}\)

Ta có: \(B=\dfrac{5}{13}\cdot\dfrac{8}{15}+\dfrac{5}{13}\cdot\dfrac{26}{15}-\dfrac{5}{13}\cdot\dfrac{8}{15}\)

\(=\dfrac{5}{13}\cdot\dfrac{26}{15}\)

\(=\dfrac{130}{195}=\dfrac{2}{3}\)

5²⁰: (5¹⁵.16+5¹⁵ .9)=5²⁰ :[5¹⁵.(16+9)]

                            =5²⁰:[5¹⁵.25]

                            =5²⁰:[5¹⁵.5²]

                            =5²⁰:5¹⁷=5²

tick nha

Câu 9

a) 2/15 + (-3/5)

= 2/15 - 3/5

= 2/15 - 9/15

= -7/15

b) -5/7 + 3/7 . (-2/9)

= -5/7 - 2/21

= -15/21 - 2/21

= -17/21

c) 5/16 - (7/15 - 3/16) + 17/30

= 5/16 - 7/15 + 3/16 + 17/30

= (5/16 + 3/16) + (17/30 - 14/30)

= 1/2 + 1/10

= 5/10 + 1/10

= 6/10

= 3/5

\(a,\dfrac{2}{15}+\left(-\dfrac{3}{5}\right)\\ =\dfrac{2}{15}-\dfrac{3}{5}\\ =\dfrac{2}{15}-\dfrac{9}{15}\\ =-\dfrac{7}{15}\\ b,-\dfrac{5}{7}+\dfrac{3}{7}\times\left(-\dfrac{2}{9}\right)\\ =-\dfrac{5}{7}-\dfrac{2}{21}\\ =-\dfrac{15}{21}-\dfrac{2}{21}\\ =-\dfrac{17}{21}\\ c,\dfrac{5}{16}-\left(\dfrac{7}{15}-\dfrac{3}{16}\right)+\dfrac{17}{30}\\ =\dfrac{5}{16}-\dfrac{7}{15}+\dfrac{3}{16}+\dfrac{17}{30}\\ =\left(\dfrac{5}{16}+\dfrac{3}{16}\right)-\left(\dfrac{17}{15}+\dfrac{17}{30}\right)\\ =\dfrac{1}{2}-\dfrac{17}{10}\\ =\dfrac{5}{10}-\dfrac{17}{10}\\ =-\dfrac{6}{5}.\)

giúp mình với

41/16

41/16

\(240:\left(5^3-5^3:5^2\right)-3^6:3^4+15\cdot11\cdot\left(13-9\right)\)

\(=240:\left(5^3-5\right)-3^{6-4}+15\cdot11\cdot4\)

\(=240\cdot\left(125-5\right)-3^2+60\cdot11\)

\(=240:120-9+60\cdot\left(10+1\right)\)

\(=2-9+600+60\)

\(=653\)

= ( 5¹⁵.5.3 + 29.5¹⁶): 5¹⁶.2⁴

= 5¹⁶(3+29) : 5¹⁶.2⁴

= 5¹⁶.2⁵ : 5¹⁶.2⁴ = 2

( vì 3+29 = 32 =2⁵)

\(=\left(-\dfrac{5}{9}-\dfrac{4}{9}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)-\dfrac{2}{11}=-\dfrac{2}{11}\)

\(\dfrac{-5}{9}+\dfrac{8}{15}+\dfrac{-2}{11}+\dfrac{4}{-9}+\dfrac{7}{15}.\\ =\left(\dfrac{-5}{9}+\dfrac{-4}{9}\right)+\left(\dfrac{8}{15}+\dfrac{7}{15}\right)-\dfrac{2}{11}.\\ =-1+1-\dfrac{2}{11}.\\ =-\dfrac{2}{11}.\)

a, \(\dfrac{3}{5}.\left(-\dfrac{8}{3}\right)-\dfrac{3}{5}:\left(-\dfrac{3}{2}\right)=\dfrac{3}{5}.\left(-\dfrac{8}{3}\right)-\dfrac{3}{5}.\left(-\dfrac{2}{3}\right)==\dfrac{3}{5}\left(-\dfrac{8}{3}-\dfrac{2}{3}\right)=\dfrac{3}{5}.\left(-\dfrac{10}{3}\right)=-2\)

b, \(-\dfrac{5}{6}.\left(-\dfrac{12}{7}\right)-\left(-\dfrac{21}{15}\right)=-\dfrac{5}{6}.\left(-\dfrac{12}{7}\right)+\dfrac{7}{5}=\dfrac{10}{7}+\dfrac{7}{5}=\dfrac{50+49}{35}=\dfrac{99}{35}\)

a: \(=\dfrac{3}{5}\cdot\left(-\dfrac{8}{3}+\dfrac{-2}{3}\right)=\dfrac{3}{5}\cdot\dfrac{-10}{3}=-2\)

c: \(=\left(0.125\right)^{650}\cdot8^{102}\)

\(=\left(0.125\cdot8\right)^{102}\cdot\left(0.125\right)^{548}\)

\(=\dfrac{1}{8^{548}}\)