Only the relevant parts of the board have been included. Please comment to tell me if I have missed any variations.
(;AW[rb]AW[qc]AW[pb]AW[rd]AB[ob]AB[nb]AB[pc]AB[pd]AB[pe]AB[qf]AB[re]AW[qh]AW[qg]AW[pg]AW[ri]AW[pi]AB[qi]AB[qj]AB[qk]AB[ph]AB[oh]AW[nc]AW[nd]AW[oe]AW[mb]AW[lc]AB[pm]AW[me]LB[pg:1]LB[oh:2]LB[qg:3]C[The sequence with 1, 2, and 3 was played. Both White 1 and 3 are mistakes, especially 3. Black to punish.]AB[qn]AB[ro]AW[mg]AW[mf]AB[li]AP[goproblems]
(;B[og];W[pf]
(;B[rg];W[of]C[White saves his big group.])
(;B[of];W[rf]
(;B[qe];W[rg]C[And if white tries to fight?]
(;B[sf];W[sg]
(;B[sh];W[se])
(;B[se];W[sh]
(;B[sj];W[rj];B[rk];W[oc];B[sk];W[od];B[si]C[Good.RIGHT])
(;B[rj];W[sj];B[sk];W[oc];B[si]C[Ko. Although this is favourable for black, black can do better.])))
(;B[se];W[sh];B[sf];W[sg]
(;B[sj];W[rj];B[rk];W[oc];B[sk];W[od];B[si]C[Good.RIGHT])
(;B[rj];W[sj];B[sk];W[oc];B[si]C[Ko. Although this is favourable for black, black can do better.]))
(;B[sh];W[se]
(;B[rh];W[sf])
(;B[sf];W[sg])
(;B[sg];W[sf]))
(;B[sg];W[sf]
(;B[se];W[sh])
(;B[sh];W[se])
(;B[rh];W[sh])
(;B[rj];W[se]))
(;B[sd];W[sf]
(;B[se];W[sh]C[This doesn't turn out to be very good for black.])
(;B[sh];W[se]))
(;B[si];W[se]))
(;B[rg];W[qe]C[];B[rh];W[qf]
(;B[qd];W[se])
(;B[sf];W[se]))
(;B[qd];W[qe]C[Ko. Not the best.]))
(;B[rh];W[of]C[White saves his big group.]))
(;B[pf];W[og]C[White escapes and black is in big trouble in the corner.])
(;B[rg];W[og]C[White escapes, for the most part.])
(;B[of];W[og]C[White escapes and black is in big trouble in the corner.])
(;B[rh];W[og]C[White escapes.]))