1. (a) Payo diagram at expiration:
20
short stock
short call
combined position
15
10
short stock
5 written call
0
−5 short stock + short call
−10
−15
−20
0 2 4 6 8 10 12 14 16 18 20
FIGURE 0.1 Payo diagram for both a short sale of stock and an at-the-money call.
i
, Payo diagram at expiration:
3.5
long put
long call
put + call
3
2.5
2
1.5
1
0.5
0
1 2 3 4 5 6 7 8 9 10
FIGURE 0.2 Payo diagram for a long put with strike K1 and a long call with strike K2 , K1 < K2 .
Payo diagram at expiration:
6
long put+short call
short put + long call
combined position
4
2
K1 K2
0
−2
−4
−6
0 2 4 6 8 10 12
FIGURE 0.3 Payo diagram for a (long put/short call) combination at K1 plus a (long call/short put) combination at K2 > K1 .
ii
, (b) Payo diagram before expiration:
10
short stock
short call
short stock combined position
5
0
−5 written call
−10
short stock + short call
−15
−20
−25
0 2 4 6 8 10 12 14 16 18 20
FIGURE 0.4 Pre-maturity payo diagram for both a short sale of stock and an at-the-money call.
Payo diagram before expiration:
4
long put
long call
put + call
3.5
3
2.5
2
1.5
1
0.5
0
0 1 2 3 4 5 6 7 8 9 10
FIGURE 0.5 Pre-maturity payo diagram for a long put with strike K1 and a long call with strike K2 , K1 < K2 .
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