cos (2x) = cos x
2 cos^2 x -1 = cos x using the double angle formula
2 cos ^2 x -cos x -1 =0
factor
(2 cos x+1) ( cos x -1) = 0
using the zero product property
2 cos x+1 =0 cos x -1 =0
2 cos x = -1 cos x =1
cos x = -1/2 cos x=1
taking the arccos of each side
arccos cos x = arccos (-1/2) arccos cos x = arccos 1
x = 120 degrees x=-120 degrees x=0
remember you get 2 values ( 2nd and 3rd quadrant)
these are the principal values
now we need to add 360
x = 120+ 360n x=-120+ 360n x = 0 + 360n where n is an integer
9514 1404 393
Answer:
117°
Step-by-step explanation:
We assume you want to report your bearing as an angle measured CW from North. For conventional angles greater than 90°, it will be ...
450° -angle = 450° -333° = 117°
The bearing of the ship is 117°.
Answer:
i think it's figure two because it has a circle at the bottom but im not too sure
Step-by-step explanation:
Answer: 10 , 13 , 14 , 15
Step-by-step explanation:
To find the perimeter of a quadrilateral , we will add all its side , that is
Perimeter = x + x + 3 + x + 4 + x + 5
That is
52 = x + x + 3 + x + 4 + x + 5
52 = 4x + 12
subtract 12 from both sides
40 = 4x
divide through by 4
x = 10
therefore , the lengths of the sides are
10 , 10+3 , 10 + 4 , 10 + 5 , that is
10 , 13 , 14 , 15
9/15. There are 15 cards and 8 of them are odd and 1 is a 2.
