f(x)=Eid.
f'(x)=dy/dx (Eid).
f'(x)=Eid ul Fitr.
f''(x)=dy/dx (Eid ul Fitr).
f''(x)=Eid ul Azha.
f'''(x)=dy/dx (Eid ul Azha).
f'''(x)=Eid ul Azha Mubarak.
Have a blesseD Eid.
May ALLAH
sh0wer his blessingz 0nt0 y0u with l0ts 0f happiness.
Engineer MSG...!