Предмет: Алгебра, автор: Daniil123466

При каких значений x имеет смысл выражения √(-x^2+3x+4)^-1

Ответы

Автор ответа: Света19999

√(-x^2+3x+4)^-1 = √1/(-x^2+3x+4)
Выражение имеет смысл если подкоренное выражение
-x^2+3x+4 > 0
D = 9 + 16 =25
x1 = (-3 + 5)/-(2) = -1 => x > -1 => 5 < x < -1
x2 = (-3-5)/(-2) = 4 => x < 5

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