i have 2v supply and rl and rc are connected across it ,the pf is given as unity how to find c,,,,? if r=2Ω ,l=1h,pf=1,c=?

 

i found z equivalent & i m confused here,,,,,that ,to equate it to real part since imaginary part is zero.on l.h.s wat is the term & whether to consider v=2?