Ta có:
49 x 62 + 38 x 73 + 31 x 51 x 2 + 19 x 27 x 2
= 49 x 62 + 38 x 73 + 62 x 51 + 38 x 27
= 62 x ( 49 + 51 ) + 38 x ( 73 + 27 )
= 62 x 100 + 38 x 100
= ( 38 + 62 ) x 100
= 100 x 100
= 10 000
49x62+38x73+31x51x2+19x27x2
= 3038+2774+3162+1026
=10000
k cho mk nha bn! :)
49 x 62 + 38 x 73 + 31 x 51 x 2 + 19 x 27 x 2
= 3038 + 38 x 73 + 31 x 51 x 2 + 19 x 27 x 2
= 3038 + 2774 + 31 x 51 x 2 + 19 x 27 x 2
= 3038 + 2774 + 3162 + 19 x 27 x 2
= 3038 + 2774 + 3162 + 1026
= ( 3038 + 3162 ) + ( 2774 + 1026 )
= 6200 + 3800
= 10000