先化简,再求值:
|
原式=
÷2(m-3) (m+2)(m-2) m(m-2)-4m+9 m-2
=
÷2(m-3) (m+2)(m-2) (m-3)2 m-2
=
•2(m-3) (m+2)(m-2) m-2 (m-3)2
=
,2 m2-m-6
∵m是方程2x2-2x-1=0的解,
∴2m2-2m-1=0,即m2-m=
,1 2
∴原式=
=-2
-61 2
.4 11
先化简,再求值:
|
原式=
÷2(m-3) (m+2)(m-2) m(m-2)-4m+9 m-2
=
÷2(m-3) (m+2)(m-2) (m-3)2 m-2
=
•2(m-3) (m+2)(m-2) m-2 (m-3)2
=
,2 m2-m-6
∵m是方程2x2-2x-1=0的解,
∴2m2-2m-1=0,即m2-m=
,1 2
∴原式=
=-2
-61 2
.4 11