Chelsea shows her work in finding the solution to 4x−5=2+3(x−3). After checking her answer in the original equation, she found that it did not work. Where did she make a mistake?

Solve 2x2 + 8 = 0 by graphing the related function. there are two solutions: . there are no real number solutions. there are two solutions: 2 and -2

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) = .

Can someone show me step by step how to do this?