kak tyt x²-x-20=0 polychilos. Created by cptleonn. algebra-ru

kak tyt x²-x-20=0 polychilos...

cptleonn @cptleonn

July 2022 1 36 Report

kak tyt x²-x-20=0 polychilos

Answers & Comments

Universalka

Verified answer

$\sqrt{x^{2} +x-21}=\sqrt{2x-1} \\\\ODZ:\\\\\left \{ {{x^{2}+x-21\geq0 } \atop {2x-1\geq 0}} \right. \\\\\Big(\sqrt{x^{2} +x-21}\Big)^{2} =\Big(\sqrt{2x-1}\Big)^{2}\\\\x^{2} +x-21=2x-1\\\\x^{2} +x-21-2x+1=0\\\\x^{2} -x-20=0\\\\D=(-1)^{2}-4\cdot(-20)=1+80=81=9^{2} \\\\x_{1} =\dfrac{1+9}{2} =5\\\\x_{2} =\dfrac{1-9}{2} =-4-neyd \ , \ tak \ kak \ 2x-1\geq0 \ , \ 2\cdot (-4)-1=-9$

1 votes Thanks 1

cptleonn Nichego cebe, ya tolko chto ponyal vsu temy kvadratnix yravnenii i sistem yravnenii spystya 1 month. Pishy na angliiskom, potomy chto pereshel na ubuntu i tyt net russkoi rasskladki klaviatury.

Answers & Comments

Verified answer

ne ponimayu kak reshat takuyu sistemu uravnenij metodom podstanovki esli v uravne

eto kak voobshe ne ponyal

otkuda eshe odna trojka vzyalas

Kak tyt 3 vishlo ne ponimau...

kak v chislitile polychilos 2v 512 obyasnite

V 3 sisteme vo 2 yravnenii kak 0,2 polychilos ne ponimau, obyasnite...

ya ne ponimayu otkuda tam vzyalas eta sistema 7 klass

otkuda oni k1 k2 2 dostali

kakim obrazom oni etu drob poluchili

perevozhu smeshannuyu drob v nepravilnuyu ne ponimayu chto tut s kornem nado delat

рекомендуемые вопросы

Helpful Links

Helpful Social