How would you verify tan3x = (3tanx - tan^3 x) / ( 1 - 3tan^2 x) and sin4x = (cosx)(4sinx - 8sin^3x) step-by-step?

Sara needs to take a taxi to get to the movies the taxi charges $4.00 for the first mile and then $2.75 for each mile after that if the total charge is $20.50 then how far was sara’s taxi ride to the movie

The boiling point of water at an elevation of 0 feet is 212 degrees fahrenheit (°f). for every 1,000 feet of increase in elevation, the boiling point of water decreases by about 2°f. which of the following represents this relationship if b is the boiling point of water at an elevation of e thousand feet? a) e = 2b - 212 b) b = 2e - 212 c) e = -2b + 212 d) b = -2e + 212

The ph level of a blueberry is 3.1 what is the hydrogen-ion concentration [h+] for the blueberry