Answer:
0.38268343
Step-by-step explanation:
cos( 67.5 )
Rewrite
67.5
as an angle where the values of the six trigonometric functions are known divided by 2 . cos ( 135\ 2)
Apply the cosine half-angle identity.
±
√
1
+
cos
(
135
)
2
Change the
±
to
+
because cosine is positive in the first quadrant.
√
1
+
cos
(
135
)
2
Simplify
√
1
+
cos
(
135
)
2
√
2
−
√
2
2
The result can be shown in multiple forms.
Exact Form:
√
2
−
√
2
2
Decimal Form:
0.38268343
…