2. (a) Use sinht- cosh t- an to show that cosh2 - sinh2t 1, d sinh t dt d cosh t dt sinh t, and lim 1+00 cosh t cosh t lim =1, t+0 cosh t (b) Let S be the parametrised surface (the pseudosphere) given by Ï(t,θ) = (coeht, cont, t-tanht) sin for 0 tand 0
