2⁴=16

3²=9

4²=16

4³=64

99⁰=1

0⁹⁹=0

1ⁿ=1

TL :

120 : 54 - [ 50 : 2 - 3² - 2 x 4 ]

120 : 54 - [ 50 : 2 - 9 - 8 ]

120 : 54 - [ 25 - 1 ]

120 : 54 - 24

120 : 30

4

120/{54-[50/2-(3^2-2*4)]}

120/{54-[50/2-(9-8)]}

120/{54-[25-1]}

120/{54-24}

120/30

4

\(=\left(-3\right)^2\left(135+130\right)+5=9.265+5=2385+5=2390\)

N = 120 . 20 = 2400 nu

A + T = 60% => A=T = 30%

G= X = 50% - 30% = 20%

A=T = 2400 x 30% = 720 nu

G=X= 2400 x 20% = 480 nu

N = 120 . 20 = 2400 nu

A + T = 60% ⇒ A=T = 30%

G= X = 50% - 30% = 20%

A=T = 2400 x 30% = 720 nu

G=X= 2400 x 20% = 480 nu

a: \(=\dfrac{6\left(12-7\right)}{60}=\dfrac{6\cdot5}{6\cdot10}=\dfrac{5}{10}=\dfrac{1}{2}\)

b: \(=\dfrac{35\cdot\left(18-1\right)}{34\cdot7}=5\cdot\dfrac{1}{2}=\dfrac{5}{2}\)

c: \(=\dfrac{42\left(1-11\right)}{21\cdot\left(-15\right)}=2\cdot\dfrac{-10}{-15}=2\cdot\dfrac{2}{3}=\dfrac{4}{3}\)

d: \(=\dfrac{2^5\cdot3^2}{2^5\cdot3^3}=\dfrac{1}{3}\)

e: \(=\dfrac{-36\cdot14}{27\left(14+7\right)}=\dfrac{-36}{27}\cdot\dfrac{14}{21}=\dfrac{-4}{3}\cdot\dfrac{2}{3}=-\dfrac{8}{9}\)

Nhanh nhé

a) (x- 35 ) - 100 = 0 

    (x- 35 )           = 0 + 100

    (x- 35 )           = 100

    x                     = 100 + 35

    x                     =   135

b) 120 + ( 118 - x ) = 213

               ( 118 - x ) = 213-120

               ( 118 - x )  = 93

                           x    = 118 - 93

                           x    = 25

c) 150 - ( x + 60 )  = 76

             ( x + 60 )   = 150 - 76

              ( x + 60 )  = 74

               x              = 74 - 60

               x              = 14

a) ( x - 35 ) - 100 = 0 

-> x - 35 - 100 = 0 

-> x - 135 = 0 

-> x = 135 

b) 120 + ( 118 - x ) = 213

-> 118 - x = 213 - 120 

-> 118 - x = 93

-> x = 118 - 93 

-> x = 25

c) 150 - ( x + 60 ) = 76

-> x + 60 = 150 - 76 

-> x + 60 = 74

-> x = 14 

CHÚC BẠN HỌC TỐT !!!  >...<

\(A=\dfrac{7}{1.9}+\dfrac{7}{9.17}+\dfrac{7}{17.25}+...+\dfrac{7}{81.89}\)

\(\dfrac{8}{7}A=\dfrac{8}{1.9}+\dfrac{8}{9.17}+\dfrac{8}{17.25}+...+\dfrac{8}{81.89}\)

\(\dfrac{8}{7}A=1-\dfrac{1}{9}+\dfrac{1}{9}-\dfrac{1}{17}+\dfrac{1}{17}-\dfrac{1}{25}+...+\dfrac{1}{81}-\dfrac{1}{89}\)

\(\dfrac{8}{7}A=1-\dfrac{1}{89}=\dfrac{88}{89}\Rightarrow A=\dfrac{88}{89}:\dfrac{8}{7}=\dfrac{77}{89}\)

\(B=\dfrac{5^2}{1.4}+\dfrac{3^2}{4.7}+\dfrac{3^2}{7.10}+...+\dfrac{3^2}{37.40}\)

\(B=\dfrac{25}{1.4}+\dfrac{9}{4.7}+\dfrac{9}{7.10}+...+\dfrac{9}{37.40}\)

\(\dfrac{1}{3}B=\dfrac{25}{12}+\dfrac{3}{4.7}+\dfrac{3}{7.10}+...+\dfrac{3}{37.40}\)

\(\dfrac{1}{3}B=\dfrac{25}{12}+\dfrac{1}{4}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{10}+...+\dfrac{1}{37}-\dfrac{1}{40}\)

\(\dfrac{1}{3}B=\dfrac{25}{12}+\dfrac{1}{4}-\dfrac{1}{40}=\dfrac{277}{120}\Rightarrow B=\dfrac{277}{120}:\dfrac{1}{3}=\dfrac{277}{40}\)

\(A=\dfrac{7}{1.9}+\dfrac{7}{9.17}+\dfrac{7}{17.25}+...+\dfrac{7}{81.89}\)

\(=7\left(\dfrac{8}{1.9}+\dfrac{8}{9.17}+\dfrac{8}{17.25}+...+\dfrac{8}{81.89}\right)\)

\(=7\left(1-\dfrac{1}{9}+\dfrac{1}{9}-\dfrac{1}{17}+\dfrac{1}{17}-\dfrac{1}{25}+\dfrac{1}{25}+...+\dfrac{1}{81}-\dfrac{1}{89}\right)\)

\(=7.\left(1-\dfrac{1}{89}\right)=7.\dfrac{88}{89}=\dfrac{616}{89}\)