Answer:
a) 8 b)9 c)1 d) 3
Step-by-step explanation:
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:
NO because 7+5=12
The sum must be larger (not equal to) the longest side. If it's exactly the same, there's no room to for the shorter two sides to angle up to form a triangle.
Answer:
B
Step-by-step explanation:
sorry if i am wrong
Answer:
0,1,2
Step-by-step explanation:
(x+2) = 2((x+1)+(x)
x+2 = 2x+2+2x
x+2 = 4x+2
-x -x
2 = 3x + 2
-2 -2
0/3 = 3x/3
0 = x
