Explicație pas cu pas:
1:(2x-6) - 13 =x-21
1:(2x-6)= x- 21+13
1: (2x-6)= x-8 |*(2x-6)
1=(x-8)(2x-6)
[tex] {2x}^{2} - 6x - 16x + 48 = 1[/tex]
[tex]{2x }^{2} - 22x + 47 = 0[/tex]
[tex]delta = {b}^{2} - 4ac[/tex]
[tex]delta = { - 22}^{2} - 4 \times 2 \times 47[/tex]
[tex]delta = 108[/tex]
[tex]x1.x2 = ( -b \frac{ + }{ - } \sqrt{delta} ) \div \: 2a [/tex]
[tex]x1.x2 = (- ( - 22) \frac{ + }{ - } \sqrt{108}) \div (2 \times 2)[/tex]
[tex]x1.x2 = (22 \frac{ + }{ - } 6 \sqrt{3} ) \div 4[/tex]
[tex]x1 = 2(11 + 3 \sqrt{3} ) \div 4 =( 11 + 3 \sqrt{3} ) \div 2[/tex]
[tex]x2 = 2(11 - 3 \sqrt{3} ) \div 4 = (11 - 3 \sqrt{3} ) \div 2[/tex]
