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Write as (a,b) = (8,-9) or (a,b) =(-9,8 ). What the solutions as written say is (8,-9) =(-9,8) which is incorrect. Also only One solution is needed Since by symmetry if (8,-9) is a solution then so is (-9,8).
@user-pd7js7cy9m14 күн бұрын
Hellooooo 😊). A bad solution to an easy problem. After 2:40 we substitute (1) a=b and (2) a=-b-1 in (0) a^2-b-73=0 . We get : (0,1) b^2-b-73=0 , and (0,2) b^2+b-72=0 . Therefore : (3) b1=[ 1-sqrt(293) ]/2 , b2=[1+sqrt(293) ]/2 (4) {thanks to Vietta } : b3=-9 , b4=8 , we substitute (3) in (1) and (4) in (2) . We get the right answer. With respect to, Lidiy
@ashtongreenidge11 күн бұрын
Recall the condition that a is not equal to b.
@soniamariadasilveira700315 күн бұрын
I loved this problem!
@Frankkusi-se2rf5 күн бұрын
Please there is a problem in the factorization
@user-ft8ws5tt1x21 сағат бұрын
В первую секунду я подумал, что a=b, и во вторую секунду меня обломали)
@LogicRk15 күн бұрын
Superb ❤
@duncan-rmi12 күн бұрын
I did it in my head. but what sort of pen is that? do they do them in other colours?
@als2cents67915 күн бұрын
In your solution validation you only plugged values in one of the simultaneous equation. You really need to plug into both of the original simultaneous equations to validate that the solution is valid.
@margotconard76448 күн бұрын
a^2 = 73 + b b^2 = 73 + a the nearest square of an interger that is larger than 73 is 81 by inspection if a equals 9 and b equals -8, the problem is solved.
Хотя есть и более простые методы решения, но эта игра с формулами мне понравилась.
@learncommunolizer4 күн бұрын
Your welcome
@evgenysapotnitsky82349 күн бұрын
Задача, на самом деле, очень простая. Вычитаем второе уравнение из первого и после преобразований получаем (a-b)(a+b+1)=0. Отсюда следует a=-1-b (a не равно b по условию задачи). Подставляем полученное выражение для "a" во второе уравнение и получаем b^2+b-72=0. Решаем квадратное уравнение и получаем ответ: 1) b=8, a=-9; 2)b=-9, a=8. Тринадцать минут на такую задачу - очевидный перебор))
@evbdevy3526 күн бұрын
Я тоже решил именно так,отнял от(1) (2).Получил такое же кв.урав-е.
@evbdevy3526 күн бұрын
Потратил не более 5 мин.На Олимп.ге тянет
@user-xq8cg3gf5f12 күн бұрын
81-8=73 64+9=73
@user-sx6vo6ne5f15 күн бұрын
:))))))))) Jak można tak rozwlekać proste zadanie ?!!! było wstawić a=-b-1 do drugiego równania i wynik gotowy z prostego równania kwadratowego b=-9 ; 8 a=8 ; -9
@YAWTon13 күн бұрын
The same problem with the same solution was uploaded to YT a short while ago. I think this guy just made a copy of that clip... terribly boring, and bad from a didactic point of view.
@lisandro7315 күн бұрын
There are two more real, when a and b are irrational
@user-xq8cg3gf5f12 күн бұрын
а=9 б=-8 !!!
@vanessawelles476015 күн бұрын
easy to guess the solution by saying what number squared is is slightly greater than 73. result -9 and 8
@salvatorechiocca237513 күн бұрын
A
@user-md4br9kj3i13 күн бұрын
Всё конечно красиво, но зачем так сильно раскладывать и расписывать очевидные вещи?
@evbdevy3526 күн бұрын
I have solved by other way.Plused (1) and (2)
@Tiberius8814 күн бұрын
Long winded. It doesn't take 13 mins to solve this!
@YAWTon13 күн бұрын
You can halve the time by playing the clip at double speed...😊