= 2pecado? (x/2)/[2xsin(x/2)cos(x/2)]
= sin(x/2)/[xcos(x/2)]
=(1/2)sin(x/2)/[(x/2)cos(x/2)]
El límite es 1/2
17.
y ' =[e^(-x/2)](-1/2)cos3x+[e^(-x/2)](-sin3x)*3
=- [ (1/2)cos3x+3sin3x][e^(-x/2)]
18.
= -(1/2)∫[e^(-x )]d(-x?)
= (-1/2)e^(-x?)|
= (e - 1/e)/2
19.
= ∫(√x - x?)dx
= [(2/3)x^(3/2) - x? /3)|
= 2/3 - 1/3
= 1/3