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
…
B. Double 5 plus 1 equals 11 and add 1 to 5 doubled equals 12.
Answer:
sin A = 13/85
Step-by-step explanation:
Opposite Angle A is side BC, of length 13. The length of the hypotenuse is 85. The sine function is defined as the ratio opp/hyp. In this problem that ratio is
opp
------ = sin A = 13/85
hyp
We use the inverse sine function arcsin x to determine Angle A:
A = arcsin 13/85 = 8.8 degrees
x=11
the angles are congruent so 6x-10=56
6x=66
x=11