Bilimlar bellashuvi va olimpiadalar

Olimpiada VII tur yechimlari (7-sinf)

1.Yechish:

X8+x+1=(x8+x7+x6)-(x7+x6+x5)+(x5+x4+x3)-(x4+x3+x2)+(x2+x+1)= x6(x2+x+1)-

-x5(x2+x+1)+x3(x2+x+1)-x2(x2+x+1)+ (x2+x+1)=(x6-x5+x3-x2+1) (x2+x+1).

  1. Yechish:

<RLS=80%<PLR  ,  <PLR= x deylik , u holda <RLS= 0,8x bo’ladi.Tenglama tuzamiz: x+0,8x= 180;   1,8x= 180;  x= 180:1,8= 100;   180-100= 80;

Javob: 1000; 800.

  1. Yechish:

= 24= 16  ⇒ 222> ;

222= 24 ⋅218= 16⋅ 218 > ;

222= 29 ⋅213= 512⋅ 213>222, chunki 222 =484.   Javob: 222> 222> .

  1. Javob: 45 va 90.
  2. Yechish:(a2-9)x=7a2-20a-3;        (a-3)(a+3)x= (7a+1)(a-3). Bundan:

Javob:  a=3 da , x∈ R; a= -3 da , ildizi yo’q;  a  ±≠3 da  .

  1. Yechish:

y= ax+5;   M(-3;2)     M ning koordinatalarini tenglikka qo’yamiz, unda

a (-3)+5=2;   a=1;       J: a= 1.

7.Yechish:

 belgilash kiritamiz , u holda    Bu yerdan a= 0,25;   b= 0,05 topilganlarni o’rniga qo’yilsa,   x=6; y= 2 chiqadi.            Javob: x=6; y=2.

8.Yechish:

(x+3)(y-2)=0;   Tenglamaning ildizlari x=-3 va y=2 . Grafik x=-3 oy o’qiga parallel va ox o’qida  x=-3dan o’tadigan to’g’ri chiziq. y= 2 to’g’ri chiziq esa, oy da y=2 dan o’tuvchi ox o’qiga paralleldir.

9.Yechish:

  ; 9x= 896-7x;  16x=896;  x= 56;  128-56=72;   J: 56; 72.

  1. Yechish:

Muallif haqida

Foziljon Anapiyayev

Andijon viloyati, Baliqchi tumani.
O‘zbekiston xalq ta’limi a’lochisi
Xozirda nafaqada.

Fikr bildiring

This site uses Akismet to reduce spam. Learn how your comment data is processed.