a)

\(15+27+9+85+73\)

\(=\left(15+85\right)+\left(27+73\right)+39\)

\(=200+39\)

\(=329\)

b)

\(54.36+54.27+54.37\)

\(=54\left(36+27+37\right)\)

\(=54.100\)

\(=5400\)

c)

\(168-3^7:3^4+2013^0\)

\(=168-3^3+1\)

\(=168-27+1\)

\(=142\)

d)

\(3^4.15+81.26+27.59.3\)

\(=81.15+81.26+81.59\)

\(=81.\left(15+26+59\right)\)

\(=81.100\)

\(=8100\)

Tính giá trị của các biểu thức sau :

a.15 + 27 + 39 + 85 + 73

= ( 15 + 85 ) + ( 27 + 73 ) + 39

= 100 + 100 + 39

= 200 + 39

= 239

b. 54 .36 + 54 . 27 + 54 . 37

= 54 . ( 36 + 27 + 37 )

= 54 . 100

= 5400

c.168 - 3⁷ : 3⁴ + 2013⁰

= 168 - 3³ + 1

= 168 - 27 + 1

= 141 + 1

= 142

đ. 3⁴ . 15 + 81 . 26 + 27 . 59 . 3

= 3⁴ . 15 + 3⁴ . 26 + 3⁴ . 59

= 3⁴ . ( 15 + 26 + 59 )

= 81 . 100

= 8100

a.15 + 17 + 39 + 85 + 73

= ( 15 + 85 ) + ( 17 + 73 ) + 39

= 100 + 90 + 39

= 229

b. 54.36+54.27+54.37

= 54.(36+27+37)

= 54.100

=5400

c.168-3^7_:3⁴+2013⁰

⁼ 168-3^7-4+1

= 168-3³+1

= 168-27+1

= 142

d.3⁴.15+81.26+27.59.3

= 3⁴.15+3⁴.26+3³.59.3

= 3⁴.15+3⁴.26+3⁴.59

= 3⁴.(15+26+59)

= 3⁴.100

= 81.100

= 8100

A = \(\dfrac{18}{26}\) + (-\(\dfrac{5}{27}\)) + (-\(\dfrac{22}{86}\)) + \(\dfrac{12}{39}\) - \(\dfrac{32}{43}\)

A = \(\dfrac{9}{13}\) - \(\dfrac{5}{27}\) -  \(\dfrac{11}{43}\) + \(\dfrac{4}{13}\) - \(\dfrac{32}{43}\)

A = (\(\dfrac{9}{13}\) + \(\dfrac{4}{13}\)) - (\(\dfrac{11}{43}\) + \(\dfrac{32}{43}\)) - \(\dfrac{5}{27}\)

A = \(\dfrac{13}{13}\) - \(\dfrac{43}{43}\) - \(\dfrac{5}{27}\)

A = 1 - 1 - \(\dfrac{5}{27}\)

A = 0 - \(\dfrac{5}{27}\)

A = - \(\dfrac{5}{27}\)

B = -\(\dfrac{10}{12}\) + \(\dfrac{8}{15}\) - \(\dfrac{19}{56}\) + \(\dfrac{3}{-18}\) + \(\dfrac{28}{60}\)

B = - \(\dfrac{5}{6}\) + \(\dfrac{8}{15}\) - \(\dfrac{19}{56}\) - \(\dfrac{1}{6}\) + \(\dfrac{7}{15}\)

B = -(\(\dfrac{5}{6}\) + \(\dfrac{1}{6}\)) - \(\dfrac{19}{56}\) + (\(\dfrac{8}{15}\) + \(\dfrac{7}{15}\))

B = -1  - \(\dfrac{19}{56}\) + 1

B = - \(\dfrac{19}{56}\) 

\(\sqrt{64}-\sqrt{169}+\sqrt{9}=8-13+3=-2\)

\(4\sqrt{3}+\sqrt{27}-\sqrt{75}=4\sqrt{3}+3-5\sqrt{3}=\sqrt{3}\left(4+3-5\right)=2\sqrt{3}\)

\(1.\) 12 x 11 + 21 x 11 x 11 + 11 x 33

= ( 12 x 11 ) + ( 21 x 11 x 11 ) + ( 11 x 33 )

= \(132+2541+363\)

= \(3036\)

132x11-11x32-54x11

= ( 132 x 11 ) - ( 11 x 32 ) - ( 54 x 11 )

\(=1452-352-594\)

= \(506\)

\(2.\)

45 x 32 + 1245

= ( 45 x 32 ) + 1245

= 1400 + 1245

= 2685

75 x 18 + 75 x 21

= ( 75 x 18 ) + ( 75 x 21 )

= 1350 + 1575

= 2925

12 x (27+46) -1567

= 12 x 73 - 1567

= ( 12 x 73 ) - 1567

= 876 - 1567

= - 691

A =\(\left(1+\frac{2}{1}\right)\left(1+\frac{2}{2}\right)\left(1+\frac{2}{3}\right)\left(1+\frac{2}{4}\right)...\left(1+\frac{2}{26}\right)\left(1+\frac{2}{27}\right)\)

\(=\frac{3}{1}.\frac{4}{2}.\frac{5}{3}.\frac{6}{4}....\frac{28}{26}.\frac{29}{27}=\frac{28.29}{1.2}=14.29=406\)

\(=1+\frac{1}{3^1}+\frac{1}{3^2}+\frac{1}{3^3}+...+\frac{1}{3^7}\)

\(=1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}+\frac{1}{243}+\frac{1}{729}+\frac{1}{2187}\)

\(=\frac{2187}{2187}+\frac{729}{2187}+\frac{81}{2187}+\frac{27}{2187}+\frac{9}{2187}+\frac{3}{2187}+\frac{1}{2187}\)

\(=\frac{2187+729+81+27+9+3+1}{2187}\)

\(=\frac{3037}{2187}\)

Đúng 100%

toán lớp 4 chưa học bình phương -.-

A = 2015 . ( 27 - 3 ) - 27 . ( 2015 - 3 ) + 2015  x 3

A = 2015 x  27 - 2015 x 3 - 27 x 2015 + 27 x 3 + 2015 x 3

A = 2015 x 27 - 27 x 2015 - 2015 x 3 + 2015 x 3 + 27 x 3

A = 0 - 0 + 27 x 3

A = 81

Ủng hộ nhé ! 

A = 2015 ( 27 - 3 ) - 27 ( 2015 - 3 ) + 2015 x 3

A = 2015 x 27 - 2015 x 3 - 27 x 2015 + 27 x 3 + 2015 x 3

A = 2015 x 27 - 27 x 2015 - 2015 x 3 + 2015 x 3 + 27 x 3

A = 0 - 0 + 27 x 3

A = 81

A=2015.(27-3)-27.(2015-3)+2015*3

A=2015*27-2015.3-27.2015+27.3+2015.3

A=2015.27-27.2015-2015.3+2015.3+27.3

A=0-0+27.3

A=0+27.3

A=0+81

A=81

23 + 39 + 37 + 21 + 34 + 26

= (23 + 37) + (39 + 21) + (34 + 26)

= 60 + 60 + 60

= 60 x 3

= 180

23 + 39 + 37 + 21 + 34 + 26

=(23 + 37) + (39 + 21) + (34 + 26)

=60 + 60 + 60

=60 × 3

=180