8 класс.помогите по фото пожалуйста. теорема виета.отдаю все баллы! с фотографией решения...

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Хуqожнuк_zn · Answer 1 · 2018-05-09T15:46:25+0000

Теорема Виета для x²+bx+c=0 :
$\left \{ {{x_1+x_2=-b} \atop {x_1x_2=c}} \right.$
Теорема Виета для ax²+bx+c=0 :
$\left \{ {{x_1+x_2= \frac{-b}{a} } \atop {x_1x_2= \frac{c}{a} }} \right.$

$x^{2} -9x+18=0 \\ \left \{ {{x_1+x_2=9} \atop {x_1x_2=18}} \right. \\ \left \{ {{x_1=3} \atop {x_2=6}} \right. \\ OTBET: 3;6 \\ x^{2} -3x-18=0 \\ \left \{ {{x_1+x_2=3} \atop {x_1x_2=-18}} \right. \\ \left \{ {{x_1=-3} \atop {x_2=6}} \right. \\ OTBET: -3;6 \\ 35 x^{2} -39x+10=0 \\ \left \{ {{x_1+x_2= \frac{39}{35} } \atop {x_1x_2= \frac{10}{35} }} \right. \\ \left \{ {{x_1= \frac{2}{5} } \atop {x_2= \frac{5}{7} }} \right. \\ OTBET: \frac{2}{5} ; \frac{5}{7}$
$63 x^{2} +61x+6=0 \\ \left \{ {{x_1+x_2= -\frac{61}{63} } \atop {x_1x_2= \frac{6}{63} }} \right. \\ \left \{ {{x_1=- \frac{1}{9} } \atop {x_2=- \frac{6}{7} }} \right. \\ OTBET: - \frac{1}{9}; - \frac{6}{7} \\ x^{2} +8x-9=0 \\ \left \{ {{x_1+x_2=-8} \atop {x_1x_2=-9}} \right. \\ \left \{ {{x_1=-9} \atop {x_2=1}} \right. \\ OTBET: 1;-9 \\ x^{2} -9x+20=0 \\ \left \{ {{x_1+x_2=9} \atop {x_1x_2=20}} \right. \\ \left \{ {{x_1=4} \atop {x_2=5}} \right. \\ OTBET: 4;5$
$72 x^{2} +23x-4=0 \\ \left \{ {{x_1+x_2=- \frac{23}{72} } \atop {x_1x_2=- \frac{4}{72} }} \right. \\ \left \{ {{x_1= \frac{1}{8} } \atop {x_2=- \frac{4}{9} }} \right. \\ OTBET: - \frac{4}{9} ; \frac{1}{8} \\ 27 x^{2} +3x-10=0 \\ \left \{ {{x_1+x_2= -\frac{3}{27} } \atop {x_1x_2=- \frac{10}{27} }} \right. \\ \left \{ {{x_1= -\frac{2}{3} } \atop {x_2= \frac{5}{9} }} \right. \\ OTBET: -\frac{2}{3} ; \frac{5}{9}$
$x^{2} +8x+12=0 \\ \left \{ {{x_1+x_2=-8} \atop {x_1x_2=12}} \right. \\ \left \{ {{x_1=-2} \atop {x_2=-6}} \right. \\ OTBET: -2;-6 \\ x^{2} +x-20=0 \\ \left \{ {{x_1+x_2=-1} \atop {x_1x_2=-20}} \right. \\ \left \{ {{x_1=-5} \atop {x_2=4}} \right. \\ OTBET: -5;4 \\ 12 x^{2} -4x-5=0 \\ \left \{ {{x_1+x_2= \frac{4}{12} } \atop {x_1x_2=- \frac{5}{12} }} \right. \\ \left \{ {{x_1=- \frac{1}{2} } \atop {x_2= \frac{5}{6} }} \right. \\ OTBET: - \frac{1}{2} ; \frac{5}{6}$
$28 x^{2} -9x-9=0 \\ \left \{ {{x_1+x_2= \frac{9}{28} } \atop {x_1x_2= -\frac{9}{28} }} \right. \\ \left \{ {{x_1=- \frac{3}{7} } \atop {x_2= \frac{3}{4} }} \right. \\ OTBET: -\frac{3}{7} ; \frac{3}{4} \\ x^{2} -7x+12=0 \\ \left \{ {{x_1+x_2=7} \atop {x_1x_2=12}} \right. \\ \left \{ {{x_1=1} \atop {x_2=6}} \right. \\ OTBET: 1;6 \\ x^{2} +2x-3=0 \\ \left \{ {{x_1+x_2=-2} \atop {x_1x_2=-3}} \right. \\ \left \{ {{x_1=-3} \atop {x_2=1}} \right. \\ OTBET: -3;1$
$18 x^{2} -17x+4=0 \\ \left \{ {{x_1+x_2= \frac{17}{18} } \atop {x_1x_2= \frac{4}{18} }} \right. \\ \left \{ {{x_1= \frac{4}{9} } \atop {x_2= \frac{1}{2} }} \right. \\ OTBET: \frac{4}{9} ; \frac{1}{2} \\ 28 x^{2} +31x+6=0 \\ \left \{ {{x_1+x_2= -\frac{31}{28} } \atop {x_1x_2= \frac{6}{28} }} \right. \\ \left \{ {{x_1=- \frac{1}{4} } \atop {x_2=- \frac{6}{7} }} \right. \\ OTBET: - \frac{1}{4} ;- \frac{6}{7}$
<img src="https://tex.z-dn.net/?f=+x%5E%7B2%7D+%2B11x%2B24%3D0+%5C%5C+%5Cleft+%5C%7B+%7B%7Bx_1%2Bx_2%3D-11%7D+%5Catop+%7Bx_1x_2%3D24%7D%7D+%5Cright.+%5C%5C+%5Cleft+%5C%7B+%7B%7Bx_1%3D-8%7D+%5Catop+%7Bx_2%3D-3%7D%7D+%5Cright.+%5C%5C+OTBET%3A+-3%3B-8+%5C%5C++x%5E%7B2%7D+-4x-12%3D0+%5C%5C+%5Cleft+%5C%7B+%7B%7Bx_1%2Bx_2%3D4%7D+%5Catop+%7Bx_1x_2%3D-12%7D%7D+%5Cright.+%5C%5C+%5Cleft+%5C%7B+%7B%7Bx_1%3D-2%7D+%5Catop+%7Bx_2%3D6%7D%7D+%5Cright.+%5C%5C+OTBET%3A+-2%3B6+%5C%5C+14+x%5E%7B2%7D+%2Bx-3%3D0+%5C%5C+%5Cleft+%5C%7B+%7B%7Bx_1%2Bx_2%3D-+%5Cfrac%7B1%7D%7B14%7D+%7D+%5Catop+%7Bx_1x_2%3D+-%5Cfrac%7B3%7D%7B14%7D+%7D%7D+%5Cright.+%5C%5C+%5Cleft+%5C%7B+%7B%7Bx_1%3D+-%5Cfrac%7B1%7D%7B2%7D+%7D+%5Catop+%7Bx_2%3D+%5Cfrac%7B3%7

Хуqожнuк_zn (25.4k баллов) 09 Май, 18