Draw the effective equivalent circuit of the circuit shown in figure at very high frequencies and find the effective impedance.

Explanation

Inductive reactance `X_L=2pivL`
Capactive reactance `X_C=1/(2pivC)`
For very high frequency `(v to oo)`
`X_L to oo` and `X_C to 0`
When reactance of a circuit is infinite it will be considered as open circuit.
When reactance of a circuit is zero it will be considered as short circuited.
So, `C_1,C_2 to` shorted and `L_1, L_2 to` opended .

So , effective impedance `Z_(eq)=R_1+R_3`