<span> 4.</span><em>2х</em><span>2 - 18x + 40 = 0; 2у2 + у - 7 = 0; 0,</span><em>5 х</em><span>2 + 3x - 8 = 0. 2. </span>...<span> 4 и -3; -</span><em>6</em><span> и </span><em>5</em><span>; 2 - и 2 + . 3.</span>...<span> Дано: ах2 + bx + c = 0, где а = </span><em>1</em><span>, x</span><em>1</em><span> и x2 –корни квадратного уравнения</span>
Решение смотрите во вложении....
ОДЗ: х≠2
х≠3
0[/tex]
Разложим на множители:
5x²-25x+31=0
D=625-4*5*31=625-620=5
x₁=(25-√5)/10≈2.27
x₂=(25+√5)/10≈2.72
+ - + - +
------- 2 ---------
(25-√5)/10 ----------- (25+√5)/10 -------- 3
----------\\\\\\\\\ \\\\\\\\\\\\\ \\\\\\\\\\\\\
x∈(-∞; 2)U[(25-√5)/10; (25+√5)/10]U(3; +∞)