S0 = aaj ka stock price (jab tumne shares kharida)
K = call ka strike price jo tumne becha
c = per share premium mila
ST = expiry par stock price
Step 1 — Stock leg se profit.
Tumne S0 par kharida, ab yeh ST worth hai:
Stock P/L=ST−S0Yeh step kyun? Stock rakhna sirf price change track karta hai, kuch fancy nahi.
Step 2 — Short call leg se profit.
Tumne creceive kiya. Call buyer tab hi exercise karta hai jab ST>K ho, aur tab tumhe usse honor karne mein (ST−K) lagta hai. Short call ka payoff:
Call P/L=c−max(ST−K,0)Yeh step kyun? Agar ST≤K toh call worthless expire hoti hai — poora c tumhare paas rehta hai. Agar ST>K toh tumhe kuch jo ST worth hai K par bechna padta hai, difference ka loss hota hai.
Step 3 — Dono legs add karo.Π(ST)=(ST−S0)+c−max(ST−K,0)
Step 4 — Dono regimes mein tod lo.
Strike ke neeche (ST≤K): max term 0 hai:
Π=ST−S0+c
Yeh ek rising line hai — agar stock badhta hai toh bhi tum gain karte ho, plus premium.
Strike ke upar (ST>K): max=ST−K:
Π=(ST−S0)+c−(ST−K)=K−S0+cST ke terms cancel ho jaate hain → profit ek flat cap ban jaata hai. Yahi "capped upside" hai.
Break-even S0−c kyun hai: premium tumhare purchase price par discount ki tarah kaam karta hai. Tumhara loss tabhi shuru hota hai jab stock neeche girta hai us price se jo tumne effectively diya.
Recall Feynman: 12 saal ke bachche ko explain karo
Socho tumhare paas ek cycle hai. Ek dost tumhe aaj $5 deta hai ek promise ke liye: "agar main chaahunga, toh agle mahine main tumhari cycle $110 mein khareed sakta hoon." Tumhe lagta hai tumhari cycle lagbhag $100 ki hai aur zyada nahi badhlegi. Toh woh $5 badhiya pocket money hai! Par agar cycle achanak super trendy ho jaaye aur $130 ki ho jaaye, toh tumhara dost isse sirf $110 mein khareeg lega — tumhe bechni padegi, aur extra value miss ho jaayegi. Woh $5 us maybe-future sale ko "rent" par dene ki fee thi. Yahi covered call hai: tumhare paas cheez hai, aur tum kisi ko woh choice bechte ho ki woh isse baad mein fixed price par khareed sake.
