问题
选择题
若函数y=4sin(2x+
|
答案
函数y=4sin(2x+
)(x∈[0,π 6
])的图象的对称轴有2条,分别为7π 6
x=
和x=π 6
,由正弦函数图象的对称性可得x1+x2=2×4π 6
=π 6
,x2+x3 =2×π 3
=4π 6
.4π 3
故x1+2x2+x3 =x1+x2+x2+x3 =
+π 3
=4π 3
,5π 3
故选C.
若函数y=4sin(2x+
|
函数y=4sin(2x+
)(x∈[0,π 6
])的图象的对称轴有2条,分别为7π 6
x=
和x=π 6
,由正弦函数图象的对称性可得x1+x2=2×4π 6
=π 6
,x2+x3 =2×π 3
=4π 6
.4π 3
故x1+2x2+x3 =x1+x2+x2+x3 =
+π 3
=4π 3
,5π 3
故选C.