Answer:
does anybody?
Step-by-step explanation:
attach work
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
$96(2 payments) = $192
$192/(12 months) = $16 per month (she should set aside)
The interest figure always means the interest for a year.
120 days is 1/3 of a year, so you'll only earn 1/3 of 6.5% .
6.5% = 0.065
1/3 of that is 0.02167 .
(0.02167) x (7,000) = 151.67