Evaluate the following : cos² pi/6 +cos² pi/2
Answers
Answered by
0
Answer:
Let us note that, because,
cos
(
−
x
)
=
cos
x
...
...
(
⋆
)
, the given expression
=
sin
2
(
π
6
)
−
2
sin
(
π
6
)
cos
(
π
6
)
+
cos
2
(
π
6
)
=
(
sin
(
π
6
)
−
cos
(
π
6
)
)
2
=
(
1
2
−
√
3
2
)
2
=
{
1
−
√
3
2
}
2
=
1
4
(
1
−
2
√
3
+
3
)
=
1
4
(
4
−
2
√
3
)
=
1
2
(
2
−
√
3
)
Answered by
0
Answer:
cos(pi/2) =0
so 0²=0
cospi/6 =root 3/2
square of root 3/2=3/4
so 3/4+0=3/4
Similar questions