Siz bu yerda saytimizda muntazam chop etilib kelinayotgan matematika fanidan 8-sinf o’quvchilariga mo’ljallangan «Olimpiada IX tur» masalalari yechimlari va izohlari bilan tanishishingiz mumkin.
Yechimlar:
1) Yechish: xy≠ 0 deb tenglikni ikkala tomonini kvadratga oshiramiz.
(x3-y3)2= 4x2y2, (x3-y3)2 +4x3y3= 4x2y2+4x3y3, (x3-y3)2= 4x2y2(1+xy), bu yerdan
2) Javob: 324.
3) Yechish:
(6x2-7x)2-2(6x2-7x)-3=0, 6x2-7x= y belgilash kiritamiz, unda tenglama y2-2y-3=0 ko’rinishga keladi.Bu tenglamani yechsak y1=3, y2=-1.O’rniga qo’ysak, 6x2-7x-3=0 va 6x2-7x+1=0 tenglamalar hosil bo’ladi. Bularni yechsak.
J: x1=1,5 ;
4) Yechish:
x2+3x+m=0 , x1-x2=6, x1= 6+x2.
x1+x2= -3, 6+x2+x2=- 3, 2x2= -9; x2= -4,5.
x1= -3-x2= -3-(-4,5) = -3+4,5= 1,5.
m=x1x2= 1,5⋅ (-4,5)= – 6,75; Javob: m= – 6,75.
5) Yechish:
Javob: (1;2), (2;1)
6) Yechish:
Shartga ko’ra sistema tuzamiz: sistemani yechsak, x=6, y= 54;
Javob: Kichigi 6 kattasi 54.
7) Intervallar usuli bilan yechsak
8) Yechish:
Sistemani 1-tengsizligini soddalashtirsak ga , 2-si esa
ga ega.Buni intervallar usuli bilan yechsak, x<-2, 0<x<2 va
kesma bilan kesishmasini olsak Javob:
9) Yechish:
ACBM parallelogramda shartga ko’ra va <ECF=600, u holda <ACE= 300.Demak, AE=0,5AC= 8 m.AEC uchburchakdan AC= 16m, AE= 8m, CE2= AC2-AE2, yoki
10)Tengsizlikninh ikkala tomoni ham musbat, u holda ikkala tomonini kvadratga oshirsak buni yechsak,