Answer:
7/25
Step-by-step explanation:
θ lies in quadrant ii
so 2θ lies in quadrant iv
csc θ=5/3
sin θ=3/5 (sin θ=1/csc θ)
[cos(α+β)=cosαcosβ-sinαsinβ]
cos (2θ)=cos(θ+θ)=cos θ cos θ-sin θ sin θ=cos² θ-sin ²θ=1-sin²θ-sin²θ=1-2sin²θ
=1-2 (3/5)²
=1-2(9/25)
=1-18/25
=(25-18)/25
=7/25
Answer:
a or c
Step-by-step explanation:
I don’t know ask for help sorry don’t blam this on me
Answer:
The answer is a
Step-by-step explanation:
<span>(A) Find the approximate length of the plank. Round to the nearest tenth of a foot.
Given that the distance of the ground is 3ft.
In order to get the length of the plank,
we can use the this one.
cos 49 = ground / plank
cos 49 = 3 / plank
plank = cos 49 / 3
plank = 0.10 ft
</span><span>(b) Find the height above the ground where the plank touches the wall. Round to the nearest tenth of a foot.
</span><span>
The remaining angle is equal to
angle = 180 - (90+49)
angle = 41
Finding the height.
tan 41 = height / ground
tan 41 = height / 3
height = tan 41 / 3
height = 0.05 ft.
(A) 0.10 feet
(B) 0.05 feet</span>
The equation is y=(-1/2)x +2