Here are two ways of paying for delivery from an online supermarket. Option A - 1.99 for each delivery.

Option B - £5.99 per month.
All deliveries are free.
Minimum contract two years.

Rachel estimates that she will need 80 deliveries over the next two years.

Which is the cheaper option for Rachel?

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) = .

Which choice has the correct steps in graphing the solution set to the following inequality? -45_> 20x-5y

Find the amplitude of a sinusoidal function that models this temperature variation