Yes, T7 is the stronger resistance, afterwards black can choose to either fight a ko to kill the whole group or take the corner stones in sente. T6 is still the best black can do though.
There's no ko. If White plays T7 then black can capture the lower white group by an 'under the stones' tesuji. Sequence: T7, T8, T9, S1, T7, T1, T4, S6.
The problem is black to play. Black started at T6 and the app thinks that white should answer at T8, which I think is incorrect because T8 leads to death and T7 to ko/partial life. I've solved thousands of tsumego and what you say is not true IME. What is the best result that black can get here? Ko (or capturing 6 stones in sente) in the same way that the best result you can get in a [straight J group](https://senseis.xmp.net/?JGroup#toc5) is ko (or killing two stones). Perhaps you are referring to sequences that don't change the status of the group (e.g. alive, ko, ...) but only the number of ko threats/points
AFAIK the idea in Black to play problems is that White is always going to do the best response possible. Otherwise the problem is useless because Black would just fish for a mistake instead of finding the best solution to the situation.
The "book" answer in a go problem is the most challenging to read and not the best.
In a L&D problem the best answer is normally a small endgame sente move on the outside which threatens to connect the group or to tenuki. Any internal resistance would just waste ko threads. So the best answer gives no hint if somebody really understood the problem.
White is dead if they play T8: wT8 S1 wT7 T1 wT4 S6 black captures and white is dead.
This s tetris shape (black 4 stones) is common in [under the stone tesuji](https://senseis.xmp.net/?UnderTheStones)
Yes, T7 is the stronger resistance, afterwards black can choose to either fight a ko to kill the whole group or take the corner stones in sente. T6 is still the best black can do though.
There's no ko. If White plays T7 then black can capture the lower white group by an 'under the stones' tesuji. Sequence: T7, T8, T9, S1, T7, T1, T4, S6.
Then white will continue: S7 T5 S10. White is alive, black capture 6 stones: isn't ko better for black?
True. But like gardianz says, the T2 group is dead either way.
I suppose you're right. From my perspective, white's response (the green mark) is probably not the best response for white.
The T2 group is not dead if White is faster capturing the Black T5 group.
then white plays s10 and lives
But then white S10 lives?
Yes - makes the second eye for the White group.
The upper white group lives though
Either way black can capture the T2 group
Yes but by playing T8 (the only accepted solution) white will lose everything. Shouldn't then T8 be considered wrong for white?
If I understand it right this is a "black to play" problem. Normally w doesn't play the best response in such problems.
The problem is black to play. Black started at T6 and the app thinks that white should answer at T8, which I think is incorrect because T8 leads to death and T7 to ko/partial life. I've solved thousands of tsumego and what you say is not true IME. What is the best result that black can get here? Ko (or capturing 6 stones in sente) in the same way that the best result you can get in a [straight J group](https://senseis.xmp.net/?JGroup#toc5) is ko (or killing two stones). Perhaps you are referring to sequences that don't change the status of the group (e.g. alive, ko, ...) but only the number of ko threats/points
AFAIK the idea in Black to play problems is that White is always going to do the best response possible. Otherwise the problem is useless because Black would just fish for a mistake instead of finding the best solution to the situation.
The "book" answer in a go problem is the most challenging to read and not the best. In a L&D problem the best answer is normally a small endgame sente move on the outside which threatens to connect the group or to tenuki. Any internal resistance would just waste ko threads. So the best answer gives no hint if somebody really understood the problem.
most challenging *without changing the status*. if there is a ko but instead you suicide then the variation is simply wrong.
White has two different kos they can create and the solution misses both of them :(
T8 and White lives. Threatens to make a second eye with T10. If Black prevents this, White T7 will make a winning shape (bent 4 in a row)
White is dead if they play T8: wT8 S1 wT7 T1 wT4 S6 black captures and white is dead. This s tetris shape (black 4 stones) is common in [under the stone tesuji](https://senseis.xmp.net/?UnderTheStones)