Question

пожалуйста, помогите​

Answer 1

$1)x {}^{2} + 5x + 7 = 0 \ D = b {}^{2} - 4ac = 5 {}^{2} - 4 times 1 times 7 = 25 - 28 = - 3 \ Пустое : множество$

$3x {}^{2} + 8x + 24 = 0 \ d = 64 - 288 = - 224 \ Пустое : множество$

$6x {}^{2} + 36x - 14 = 0 | div 2 \ 3x {}^{2} + 18x - 7 = 0 \ d = (18) {}^{2} - 4 times 3 times ( - 7) = 408 = 2 sqrt{102} \ x1 = frac{ - 18 + 2 sqrt{102} }{6} = frac{ - 9 + sqrt{102} }{3} \ x2 = frac{ - 18 - 2 sqrt{102} }{6} = frac{ - 9 - sqrt{102} }{3}$

$9x {}^{2} + 81x - 64 = 0 \ d = 81 {}^{2} - 4 times 9 times ( - 64) = 6561 + 2304 = 8865 \ x1 = frac{ - 81 + 3 sqrt{985} }{18} = frac{ - 27 + sqrt{985} }{6} \ x2 = frac{ - 18 - 3 sqrt{985} }{18} = frac{ - 27 - sqrt{985} }{6}$

$36x {}^{2} + 75x + 4 = 0 \ d = sqrt{5049} = 3 sqrt{561} \ x1 = frac{ - 75 + 3 sqrt{561} }{72} = frac{ - 25 + sqrt{561} }{24} \ x2 = frac{ - 75 -3 sqrt{561} }{72} = frac{ - 25 - sqrt{561} }{24}$

$16x {}^{2} + 33x + 28 = 0 \ d = sqrt{ - 703} \ Пустое : множество$