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
3^2 + 4^2 = 5^2
65/5=13
3x13 =39
4 x 13= 42
The answer is c.2 I hope it’s right
Answer:
<em>g(x) = </em>
<em> - 3 </em>
Step-by-step explanation:
<em>g(x) = </em><em> - 3 </em>
9*13=117
12*16=192
We increased three meters to both the length and width of the garden.
