问题
解答题
计算: (1)(
(2)已知x=2+
|
答案
(1)(
+48 1 4
)÷6
,27
=
+48 27 1 4
,6 27
=
+16 9 1 4
,2 9
=
+4 3 1 12
;2
(2)x2-y2,
=(x+y)(x-y),
=(2+
+2-5
)(2+5
-2+5
),5
=8
.5
计算: (1)(
(2)已知x=2+
|
(1)(
+48 1 4
)÷6
,27
=
+48 27 1 4
,6 27
=
+16 9 1 4
,2 9
=
+4 3 1 12
;2
(2)x2-y2,
=(x+y)(x-y),
=(2+
+2-5
)(2+5
-2+5
),5
=8
.5