=202*6,25+202*2,5+202*1,25+1

=2020+1

=2021

      \(202x\frac{3}{4}+202x\frac{5}{4}+202x8\)

\(=202x\left(\frac{3}{4}+\frac{5}{4}+8\right)\)

\(=202x\left(\frac{8}{4}+8\right)\)

\(=202x\left(2+8\right)\)

\(=202x10\)

\(=2020\)

\(=202*(\frac{3}{4}+ \frac{5}{4}+8) = 202*9 = 1818\)

    202 x \(\frac{3}{4}\) + 202 x\(\frac{5}{4}\) + 202 x 8

= 202 x ( \(\frac{3}{4}\)+\(\frac{5}{4}\)+ 8 )

= 202 x ( \(\frac{8}{4}\)+ 8 )

= 202 x ( 2 + 8 )

= 202 x 10

= 2020 . 

Nhiều quá

a)202³⁰³=(202³)¹⁰¹=8242408¹⁰¹

303^202=(302^2)^101=91204^101

Vì 824208^101>91204^101=>202^303>303^202

a, 2019 x (2 x 5)

= 2019 x 10

= 20 190

b, (5 x 2) x (8 x 125) x 9

= 10 x 1000 x 9

= 90 000

c, (4 x 25) x 2019

= 100 x 2019

= 201 900

d, (50 x 2) x (125 x 8) x 202

= 100 x 1000 x 202

= 20 200 000

a) 2019 x 2 x 5

= (2 x 5) x 2019

= 10 x 2019

b) 5 x 8 x 9 x 2 x 125

= (5 x 2) x (125 x 8) x 9

= 10 x 1000 x 9

= 10000 x 9

= 90000

c) 4 x 2019 x 25

= (4 x 25) x 2019

= 100 x 2019

= 201900

d) 50 x 125 x 2 x 8 x 202

= (50 x 2) x (125 x 8) x 202

= 100 x 1000 x 202

= 100000 x 202

= 20200000

(50x2)x(125x8)x202

=100x1000x202

=202000

 50 x 125 x 2 x 8 x 202
= (50 x 2) x (125 x 8) x 202
= 100 x 1000 x 202
= 100000 x 202
= 20200000
 

=(50x2)x(125x8)x202

=100x1000x202=100 000x202=202 00000

a) 407 + 24 + (-407) + (-84)

= [407 + (-407)] + 24 + (-84)

= 0 + 24 + (-84)

= 24 + (-84)

= (-60)

b) (-42) x 23 + 77 x (-42) - 200

= (-42) x (23 + 77) - 200

= (-42) x 100 - 200

= (-4200) - 200

= (-4400)

c) (-2021) + (499 + 2021) + 41

= (-2021) + 499 + 2021 + 41

= [(-2021) + 2021] + 499 + 41

= 0 + 499 + 41

= 499 + 41

= 540

d) (-202) - (34 - 202) - 66 + 50

= (-202) - 34 + 202 - 66 + 50

= [(-202) + 202] - 34 - 66 + 50

= 0 - 34 - 66 + 50

= (-34) - 66 + 50

= (-100) + 50

= (-50)

e) Bạn viết lại đề bài.

em nên gõ công thức trực quan để được hỗ trợ tốt nhất nhé

       D =           \(\dfrac{1}{7^2}\) - \(\dfrac{2}{7^3}\) + \(\dfrac{3}{7^4}\) - \(\dfrac{4}{7^5}\) +........+ \(\dfrac{201}{7^{202}}\) -  \(\dfrac{202}{7^{203}}\)

7 \(\times\) D  =  \(\dfrac{1}{7}\) -  \(\dfrac{2}{7^2}\) +  \(\dfrac{3}{7^3}\) - \(\dfrac{4}{7^4}\)  + \(\dfrac{5}{7^5}\) -.......- \(\dfrac{202}{7^{202}}\)

7D +D  =   \(\dfrac{1}{7}\) - \(\dfrac{1}{7^2}\) + \(\dfrac{1}{7^3}\) - \(\dfrac{1}{7^4}\) + \(\dfrac{1}{7^5}\) -.........-\(\dfrac{1}{7^{202}}\) - \(\dfrac{202}{7^{203}}\)

         D = (  \(\dfrac{1}{7}\) - \(\dfrac{1}{7^2}\) + \(\dfrac{1}{7^3}\) - \(\dfrac{1}{7^4}\) + \(\dfrac{1}{7^5}\) -.........-\(\dfrac{1}{7^{202}}\) - \(\dfrac{202}{7^{203}}\)) : 8

Đặt    B =      \(\dfrac{1}{7}\) - \(\dfrac{1}{7^2}\) + \(\dfrac{1}{7^3}\) - \(\dfrac{1}{7^4}\) + \(\dfrac{1}{7^5}\) -........+\(\dfrac{1}{7^{201}}\).-\(\dfrac{1}{7^{202}}\) 

  7   \(\times\) B = 1 - \(\dfrac{1}{7}\)+\(\dfrac{1}{7^2}\) - \(\dfrac{1}{7^3}\) + \(\dfrac{1}{7^4}\) - \(\dfrac{1}{7^5}\) +.........- \(\dfrac{1}{7^{201}}\)

7B + B   =  1 - \(\dfrac{1}{7^{202}}\)

          B   =  ( 1 - \(\dfrac{1}{7^{202}}\)) : 8

         D  =  [ ( 1 - \(\dfrac{1}{7^{202}}\)): 8  - \(\dfrac{202}{7^{203}}\)] : 8 

          D = \(\dfrac{1}{64}\) - \(\dfrac{1}{64.7^{202}}\) - \(\dfrac{202}{7^{203}.8}\) < \(\dfrac{1}{64}\)