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
Answer would be eight because you divide eight hundred by ten cents to get eight.
B because 2 and 1/3 is 7/3 as an improper fraction times 4 is 28/3 and as a mixed number it is 9 and 1/3
Yes it is linear
It is a negative slope
I am attaching pic of graph
The slope is -3/4
Y intercept is (0,2)