Для того что бы нам найти значение данного выражения 3 * а^2 - а/4 нам нужно подставить известные нам величины а, которое равно а = 1/3 и выполнить определенные действия умножения, поднесение к степени.Давайте теперь подставим значение а = - 0,5 в наше выражение, тогда получаем:
S3: which kind of sports is your favourite? S1: Oh, I lobe hockey. I know everything about it. It's a winter sport, but simetimes people play it even when it's summer or autumn. S3: and you, S2? S2: well, I hate hockey. It's very dangerous to play in it, though sometimes games can be quite interesting. I love swimming. It's great to swim and relax in the same time. I love this feeling of relaxing and training [in the same time]. S1: oh, and you, S3? Which kind of sports do you prefer? S3: Frankly speaking, I like sport(s) but I didn't really know what I should choose. Can you help with that choice? S1: Yes, of course. Let's talk about it a bit later. S3+S2: Ok. See you then(,)guys. Bye.
(√7+√3)²-2√21=7+2√7·3+3-2√21=10+2√21-2√21=10