问题
解答题
(1)计算:|-4|+(
(2)先化简,再求值:(3+m)(3-m)+m(m-6)-7,其中m=
|
答案
(1)|-4|+(
+1)0-2
=4+1-212
=5-23
;3
(2)原式=(3+m)(3-m)+m(m-6)-7
=9-m2+m2-6m-7=2-6m,
当m=
时,原式=2-6×1 2
=-1.1 2
(1)计算:|-4|+(
(2)先化简,再求值:(3+m)(3-m)+m(m-6)-7,其中m=
|
(1)|-4|+(
+1)0-2
=4+1-212
=5-23
;3
(2)原式=(3+m)(3-m)+m(m-6)-7
=9-m2+m2-6m-7=2-6m,
当m=
时,原式=2-6×1 2
=-1.1 2