Question

Решите уравнения (a - 3)^2 - (a + 8) = 0

Answer 1

Решение:
$(a - 3) ^{2} - (a + 8) = 0 \\ {a}^{2} - 6a + 9 - a - 8 = 0 \\ {a}^{2} - 7a + 1 = 0 \\ d = 49 - 4 \times 1 \times 1 = 45 \\ a = \frac{7 + \sqrt{45} }{2}.a = \frac{7 + 3 \sqrt{5} }{2} \\ a = \frac{7 - \sqrt{45} }{2} .a = \frac{7 - 3 \sqrt{5} }{2}$