题目内容
(5x2-4y2)(-5x2+4y2)运算的结果是( ).A.-25x4-16y4 B.-25x4+40x2y2-16y2
C.25x4-16y4 D.25x4-40x2y2+16y2
答案:B
提示:
提示:
| (5x2-4y2)=-(-5x2+4y2) |
练习册系列答案
相关题目
题目内容
(5x2-4y2)(-5x2+4y2)运算的结果是( ).A.-25x4-16y4 B.-25x4+40x2y2-16y2
C.25x4-16y4 D.25x4-40x2y2+16y2
| (5x2-4y2)=-(-5x2+4y2) |