The expression cos^2 − cos 2 is equivalent to
(1) sin^2
(2) − sin^2
(3) cos^2 + 1
(4) − cos^2 − 1

Sandy is upgrading her internet service. fast internet charges $20 for installation and $52.45 per month. quick internet has free installation but charges $57.45 per month. part 1 out of 2 complete the equation that can be used to find the number of months after which the internet service would cost the same. use the variable x to represent the number of months of internet service purchased.