Question

Допоможіть будьласка,СРОЧНООО!

Answer 1

$\sqrt[3]{x + 7} - \sqrt{x + 3} = 0 \\ \sqrt[3]{x + 7} = \sqrt{x + 3} \\ ( \sqrt[3]{x + 7} ) {}^{6} = ( \sqrt{x + 3} ) {}^{6} \\ (x + 7) {}^{2} = (x + 3) {}^{3} \\ {x}^{2} + 14x + 49 = {x}^{3} + 9 {x}^{2} + 27x + 27 \\ x {}^{3} + 9 {x}^{2} + 27x + 27 - {x}^{2} - 14x - 49 = 0 \\ {x}^{3} + 8 {x}^{2} + 13x - 22 = 0 \\ (x - 1)( {x}^{2} + 9x + 22) = 0 \\ 1) \: \: x - 1 = 0 \\ x = 1 \\ 2) \: \: {x}^{2} + 9x + 22 = 0 \\ d = 9 {}^{2} - 4 \times 22 = 81 - 88 = - 7 \\ d < 0$

во втором случае нет корней, поэтому ответ 1