i and j are unit vectors in the x and y directions.

和 j 分别是 x 和 y 方向上的单位矢量

耶鲁公开课 - 基础物理课程节选

The struggling smartphone maker has seen its BlackBerry unit sales fall y-o-y for the last five consecutive quarters.

FORBES: RIM Manages To Conserve Cash As It Prepares For BB10 Launch Next Year

Anyone with information is asked to contact the South Wales Police Roads Policing Unit at Gwaelod y Garth on 01656 655555 extension: 42331.

BBC: Joshua Williams

The airline estimates non-fuel unit costs to be 1% higher in Q3 on a y-o-y basis.

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