( 1+3+5+7+…+2003+2005) x (125 125 x 127 – 127 127 x 125)

= ( 1+3+5+7+…+2003+2005) x (125 x 1001 x 127 – 127 x 1001x 125)

=  ( 1+3+5+7+…+2003+2005) x                   0  =    0

Vì 125 125x127 – 127 127x125 = 1001x125x127 – 1001x127x125 = 0                     

     nên : (1+3+5+...+2005)(125 125x127 – 127 127x125) = 0

bài 1 : 0

bài 2 : ( 8.78 + 1.25 ) x y= 26.3

               10.03 x y = 26.3

                         y = 26.3 : 10.03 

                        y = 2630/1003

bài 3 :diện tích HTG ABC là :

             12 x 18 : 2 = 108 ( cm2 )

      quên rùi

Đề bài có lẽ sai thừa số thứ hai phải là 125125x127-127127x125

Khi đó thừa số thứ hai sẽ là

125x1001x127-127x1001x125=0

Tích trên sẽ bằng 0
 

=0 vì thừa số sau bằng 0 nên tích bằng 0

(1+3+5+7+...+2003+2005)×(125125×127-127127×125)

=(1+3+5+7+...+2003+2005)×0

=0

Ủng hộ nhé

( 1 + 3 + 5 + 7 + ... + 2003 + 2005 ) x 125125 x127 - 127127 x 125

= ( 1 + 3 + 5 + 7 + ... + 2003 + 2005 ) x ( 125 x 1001 x 127 ) - ( 127 x 1001 x 125 )

= ( 1 + 3 + 5 + 7 + ... + 2003 + 2005 ) x 0

= 0

các bạn ơi,sửa cho mình la 125 125x127 nhé

( 1 + 3 + 5 + 7 +... + 2003 + 2005 ) x ( 125125 x 127 - 127127 x 125 )

= ( 1 + 3 + 5 + 7 + ... + 2003 + 2005 ) x ( 125 x 1001 x 127 - 127 x 1001 x 125 )

= ( 1 + 3 + 5 + 7 + ... + 2003 + 2005 ) x 0

= 0

~ Thiên Mã ~

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1. (1 + 3 + 5 + ... + 2005) . ( 125125.127 - 127127.125)

Ta có 125125.127 - 127127.125

=125.1001.127 - 127.1001.125

=0

=> (1 + 3 + 5 + ... + 2005) . ( 125125.127 - 127127.125)

= (1 +3 + 5 +...+ 2005) . 0

=0

Bài 1:

\(\left(1+3+5+...+2005\right)\cdot\left(125125.127-127127.125\right).\)

\(=\left(1+3+5+...+2005\right)\left(125.1001.127-127127.125\right).\)

\(=\left(1+3+5+...+2005\right)\left(125.127127-127127.125\right).\)

\(=\left(1+3+5+...+2005\right).0=0.\)

Vậy.....

Bài 2:

\(\left(7.13+8.13\right):\left(\dfrac{29}{3}-x\right)=39.\)

\(\left[\left(7+8\right)13\right]:\left(\dfrac{29}{3}-x\right)=39.\)

\(\left[15.13\right]:\left(\dfrac{29}{3}-x\right)=39.\)

\(195:\left(\dfrac{29}{3}-x\right)=39.\)

\(\dfrac{29}{3}-x=195:39.\)

\(\dfrac{29}{3}-x=5.\)

\(\Rightarrow x=\dfrac{29}{3}-5.\)

\(\Rightarrow x=\dfrac{29}{3}-\dfrac{15}{3}=\dfrac{14}{3}.\)

Vậy.....

~ Hok tốt!!! ~