问题
解答题
计算: (1)(3
(2)
(3)(
(4)(
|
答案
(1)(3
-4ax
)(3by
+4ax
)=(3by
)2-(4ax
)2=9ax-16by;by
(2)
(2+3
-6
)=23
+33
-3;2
(3)(
-2
+3
)(5
+2
-3
)=(5
)2-(2
-3
)2=2-3-5+25
=-6+215
;15
(4)(
-1)(2
)2=(2+1
-1)×3=32
-3.2