B1. y = 4 - x²
y = 4 - x², x = 1
y = 4 - 1² = 4 - 1 = 3
Ответ N (1; 3)
B2. 2cb⁵ - 162bc = 2bc(b⁴ - 81)
B3. 7 - (x + 2)² = 11 - x²
7 - (x + 2)² = 11 - x²
7 - (x² + 4x + 4) = 11 - x²
7 - x² - 4x - 4 = 11 - x²
-x² - 4x + x² = 11 - 7 + 4
-4x = 8 | × (-1)
4x = -8 | : 4
x = -2
B4. y = 21, y = 4x + 5
y = 4x + 5, x = 4
y = 4 × 4 + 5 = 21
A (0; 21)(4; 21)
Это задание решается через систему:
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