When he was young, Albert Einstein A did not go to school B was not good at math C had to take an exam - id1375150420230214 от rfbbfr 14.02.2023 05:11

Question

Алгебра: When he was young, Albert Einstein A did not go to school B was not good at math C had to take an exam twice D was better at home subjects than others In text B, the writer suggests that  A a scientist did not check his research B reporters might have made a mistake C the human brain is not always active D humans use 90% of their brains In text C, the writer says that  A there is some truth in the story B Newton often lied about his theories C the story is not very well known D Newton never watched

rfbbfr · Accepted Answer

X+y^2=3
x^4+y^4+6x=29
Решать будем подстановкой. Подстановку сделаем из 1-го уравнения:
у² = 3 - х
Подставим во 2-е уравнение. Получим:
х⁴ +(3 -x)² +6x -29 = 0
x⁴ +9 -6x + x² +6x -29= 0
x⁴ +x² -20 = 0
Это биквадратное уравнение. х² = t
t² + x - 20 = 0
По т. Виета t₁ = -5, t₂ = 4
x² = t
a) x² = -5
нет решений.
б) х² = 4
х = +-2
Теперь будем х = +- 2 подставлять в 1-е уравнение ( можно и во 2-е)
2 + у² = 3 -2 +у² = 3
у² = 1 у² = 5
у = +-1 у = +-√5
ответ(2;1); (2;-1); (-2;√5); (-2; -√5)

MOGZ ответил