问题
计算题
(5x+3y)(3y﹣5x)﹣(4x﹣y)(4y+x)
答案
解:(5x+3y)(3y﹣5x)﹣(4x﹣y)(4y+x),
=9y2﹣25x2﹣(16xy+4x2﹣4y2﹣xy),
=9y2﹣25x2﹣15xy﹣4x2+4y2,
=13y2﹣29x2﹣15xy.
(5x+3y)(3y﹣5x)﹣(4x﹣y)(4y+x)
解:(5x+3y)(3y﹣5x)﹣(4x﹣y)(4y+x),
=9y2﹣25x2﹣(16xy+4x2﹣4y2﹣xy),
=9y2﹣25x2﹣15xy﹣4x2+4y2,
=13y2﹣29x2﹣15xy.