Question

( 19991999 x 1998 - 19981998 x 1999 )

Answer 1

19991999 x 1998 - 19981998 x 1999

=(19990000+1999)x1998-(19980000+1998)x1999

=(1999x1000+1999x1)x1998-(1998x1000+1998x1)x1999

=1999x(1000+1)x1998-1998x(1000+1)x1999

=1999x1001x1998-1998x1001x1999

=0

Answer 2

= 0 dễ mà khỏi cần tính 

Answer 3

(19991999.1998-19981998.1999)

=3,9944014_x10¹⁰-3,9944014x10¹⁰

=                      0

chuc bn hoc gioi!

Answer 4

79888028004

Answer 5

=1999x10001x1998-1998x10001x1999

=0

Answer 6

\(19991999.1998-19981998.1999\)

\(=1999.10001.1998-1998.10001.1999\)

\(=0\)

Answer 7

(19991999x1998-19981998x1999)

=(1999x10001x1998)-(1998x10001x1999)

=0

k nha