题目错得很离谱,-√2≤sin a+cos a≤√2
要是按照题意来
sin a+cos a=2
(sin a+cos a)²=2²
sin²a+cos²a+2sin acos a=4
1+2sin acos a=4
sin acos a=3/2
tan a+cot a
=sin a/cos a+cos a/sin a
=(sin²a+cos²a)/sin acos a
=1/sin acos a
=2/3
若sin a+cos a=2,则tan a+cot a=
若sin a+cos a=2,则tan a+cot a=
A.1 B.-根号2 C.3/2 D.2/3
A.1 B.-根号2 C.3/2 D.2/3
数学人气:424 ℃时间:2020-01-30 02:06:13
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