The zero product property indicates that if “ab = 0,” then ___?___ = 0 or ___?___ = 0. Substitute the correct variable for the question mark. Select one:

a

b

a ; b

none of the above

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Which number line represents the solution set for the inequality - x 24?

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) = .