"Doesn't it taste good?"
Nope, it's a question of confirmation. "Isn't it tasty?" The negation makes it more polite.
while you are technically correct, it is more polite and common in japanese to ask for confirmation using negative forms, such as making a request with -ませんか. i.e. "走りませんか" - shall (we) go for a run?
Im pretty sure Duolingo is right about this one - but they don't offer grammar explanations so if you have limited outside experience you won't be getting the subtle difference.
In sentences such as this one; using a negative adjective (adj + ない ending), and ending with a question か plus rising intonation in spoken language, requests agreement (i.e. "isn't it", "doesn't it", etc).
Versus asking if something is not alright I feel would be along the lines of an 〜ありませんですか ending.
I could always be wrong, but I'm pretty sure to ask if something is not tasty versus asking for agreement would be "おいしいではありませんですか"
Your statement makes more of an assumption that it does taste good. The ne is really only looking for a polite agreement. The provided sentence is more tentaitive and seeking an answer from the other party, albiet in an inderect and polite way.
Formality, you'd say the affirmative to kids or close friends, and the negative toward someone you just met at a "group date".
It really doesn't differ. It just sounds poor when translated into English. おいしいですね is more common. Hope this helps!
I agree with osoikoibito. The following 2 sentences have different meanings: Doesn't it taste good? Does it not taste good?
This is where duolingo confuses me. I have always thought that the negative form of adjectives in Jap translate to NOT+adjective. Because in class we have sometimes used the negative adjective form interchangeably with the antonym e.g. not expensive = cheap; yes it's not completely the same but it depends on the context.
Your statement means, "It's good, right?" The statement is specifically talking about how something tastes.
This tripped me up because if I wanted an honest opinion about my dish, I'd ask "Is it good?"/おいしですか? rather than fish for a compliment with "Does it not taste good?"/ おいしくないですか?