Tara's car accelerated from 10 miles per hour to 70 miles per hour in 12 seconds.

what is the approximate rate of change in the miles per hour that tara's car accelerated?
a) 5 miles per hour per second
b) 8 miles per hour per second
c) 18 miles per hour per second
d) 48 miles per hour per second

Desmond wants to sell his car that he paid $8,000 for 2 years ago. the car depreciated, or decreased in value, at a constant rate each month over a 2-year period. if x represents the monthly depreciation amount, which expression shows how much desmond can sell his car for today? 8,000 + 24x 8,000 − 24x 8,000 + 2x 8,000 − 2x

Prove (a) cosh2(x) − sinh2(x) = 1 and (b) 1 − tanh 2(x) = sech 2(x). solution (a) cosh2(x) − sinh2(x) = ex + e−x 2 2 − 2 = e2x + 2 + e−2x 4 − = 4 = . (b) we start with the identity proved in part (a): cosh2(x) − sinh2(x) = 1. if we divide both sides by cosh2(x), we get 1 − sinh2(x) cosh2(x) = 1 or 1 − tanh 2(x) = .

With both problems. a.s.a.p directions on photo ^