问题
解答题
(1)解方程:2x2-2
(2)解方程:x2+4x-6=0. |
答案
(1)2x2-2
x+1=0,3
b2-4ac=(-2
)2-4×2×1=4,3
x=
,2
±3 4 2×2
x1=
,x2=
+13 2
.
-13 2
(2)x2+4x-6=0,
b2-4ac=42-4×1×(-6)=40,
x=
,-4± 40 2×1
x1=-2+
,x2=-2-10
.10
(1)解方程:2x2-2
(2)解方程:x2+4x-6=0. |
(1)2x2-2
x+1=0,3
b2-4ac=(-2
)2-4×2×1=4,3
x=
,2
±3 4 2×2
x1=
,x2=
+13 2
.
-13 2
(2)x2+4x-6=0,
b2-4ac=42-4×1×(-6)=40,
x=
,-4± 40 2×1
x1=-2+
,x2=-2-10
.10