Anna has a box that contains 4 red marbles and 3 green marbles. All of the marbles are the same size. Without looking inside the box, what is the probability she will draw a red marble from the box, and then,
without replacing the first marble, draw another red marble?
A 1 / 2 B. 2/7 C. 4/7 D. 5/9

The solution set for 5v2 – 125 = 0 is

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) = .

Multiplying fractions by whole number 5 x 1/3=?