Question

Tìm x biết ( 2x +1 ) + ( 2x +) +...+ ( 2x + 2015) = 0

Answer 1

(2x + 1) + (2x + 2) + ... + (2x + 2015) = 0

=> 2x + 1 + 2x + 2 + ... + 2x + 2015 = 0

=> 2015 . 2x + (1 + 2 + ... + 2015) = 0

=> 4030x + (2015 + 1).2015 : 2 = 0

=> 4030x + 2031120 = 0

=> 4030x = -2031120

=> x = -504

Answer 2

-504 nhé bạn

duyệt đi

Answer 3

=> ( 2x + 2x + ... + 2x + 2x ) + ( 1 + 2 + ... + 2014 + 2015 ) = 0

=> ( 2x.2015 ) + { [ 2015 . ( 2015 + 1 ) ] : 2 } = 0

=> 4030x + [ ( 2015 . 2016 ) : 2 ] = 0

=> 4030x + 2031120 = 0

=> 4030x = - 2031120

=> x = - 2031120 : 4030

=> x = - 504

Vậy x = - 504