2.18 and 2.19 C

18. Express the following in terms of x(t) : (a) y(t)=x()[(+5)(5)]d (b) y(t)=x(t)ej/2(2t3)dt c) Evaluate the following integrals: (i) cos(2t)(t)dt (ii) cos[2(t/4)](t/4)dt (iii) sin(2t)(t/6)dt (iv) sin[(t/4)](t/2)dt (v) sin[(t/6)](2t2/3)dt