计算: (1)(-12)÷4×(-6)÷2; (2)(-
(3)(-1
(4)(-3)2÷2
(5)|
(6)1+3+5+…+99-(2+4+6+…+98). |
(1)原式=(-12)×
×(-6)×1 4 1 2
=(-3)×(-6)×1 2
=18×1 2
=9;
(2)原式=(-
)×16-5 8
×(-5)×(-4)2×(-4)1 4
=-10-80
=-90;
(3)原式=-
-3 2
-5 4
+5 2
+15 4 5 4
=(-
-3 2
)-(5 2
-5 4
-15 4
)5 4
=-4+15 4
=-
;1 4
(4)原式=9×
×4 9
+4-4×(-4 9
)1 3
=
+4+16 9 4 3
=
+416+12 9
=
;64 9
(5)原式=|
+4 5
×(-12)×2 3
-9|+|24+9|×(-5)1 6
=|
-4 5
-9|+|33|×(-5)4 3
=|-9
|-1658 15
=-155
;7 15
(6)原式=1+(3-2)+(5-4)+…+(99-98)
=1+1+1+…+1
=50.