Convert the ratio gain A = vout / vin = 1.14 to dB

dB=20 log (Vo/Ein)
dB=20 log (1.14)
dB=1.138

can dB really be exactly the same as the ratio gain here?


then


Convert the voltage gain A = - 1.37 dB to ratio gain.

the only equation listed in my textbook that has Av in it is this one

-3dB = 20 log (Av)

but its not possible to log a negative number. what equation am I supposed to use?

 

can dB really be exactly the same as the ratio gain here?

Looks like it.

What you have is the 'intersection' of two functions

y=Av and y=20log(Av)

consider the functions

y=x and y=x^2 which have the same value when x=1


Av[dB]=-1.37dB

Av=10^(Av[dB]/20)=10^(-0.0685)=0.854