Điền vào chỗ trống:
1) ( .... + .....) ( 9x3 - ..... + 1) = ( .....)3+ (.....)3
2) ( x + ....) (.... -..... + 16 ) = (.....)3 + (....)3
3) ( ....+ ...) ( 25x2 - 10xt + ...) = ( ....)3+ ( ....)3
4) ( .....+.....) (.... - 6x +9 ) = (.....)3+ (....)3
5) (..... + ....) ( ..... - 12xt + ....) + (.....)3 + (....)3