428. (Og'zaki.) Ushbu geometrik progressiyaning birinchi hadi va maxraji nimaga teng:  

1) 8, 16, 32,...; 2) -10, 20,-40,...;

3) 4, 2, 1, ...; 4) -50, 10,-2,...?

429. Agar geometrik progressiyada: 

1) b₁=12, q=2; 2) b₁=-3, q = -4

bo'lsa, uning dastlabki beshta hadini yozing.

430. n-hadining formulasi bilan berilgan quyidagi ketma-ketlik geometrik progressiya bo'lishini         isbotlang:

   1) ;    2) ;     3)             4) .

431. Geometrik progressiyada:

1) b₁ =3 va q =10 bo`lsa, b₄ ni;

2) b₁ =4 va q = bo`lsa, b₇ ni;

3) b₁ =1 va q =-2 bo`lsa, b₅ ni;

4) b₁ =-3 va q = bo`lsa, b₆ ni hisoblang.

432. Geometrik progressiya n-hadining formulasini yozing:

1) 4, 12, 36,...; 2) 3, 1, ,...;

3) 4, -1, , ...; 4) 3, -4, ,...?

433. Geometrik progressiyada tagiga chizilgan hadning nomerini toping: 

1)   6, 12, 24,..., 192,…; 2) 4, 12,36,...,324,…;

3) 625, 125, 25, ...,; 4) -1, 2,-4,..., 128,… .

434. Agar geometrik progressiyada:

1) b₁=2, b₅ =162; 2) b₁ =-128, b₇ = -2;

3) b₁=3, b₄=81;  4) b₁=250, b₄= -2

bo'lsa, uning maxrajini toping.

435. 2, 6, 18, ... geometrik progressiya berilgan. 1)  shu progressiyaning sakkizinchi hadini hisoblang;  2)  ketma-ketlikning 162 ga teng hadining nomerini toping.

436. Agar musbat hadli geometrik progressiyada:  1) b₈=, b₆=81; 2)      b₆=9, b₈ =3 bo'lsa, uning yettinchi hadini va maxrajini toping.

437. Agar geometrik progressiyada:   l)       b₄ = 9, b₆ = 20; 2) b₄ = 9,b₆ = 4    bo'lsa, uning beshinchi va birinchi hadlarini toping.

438. Omonatchi jamg`arma bankiga 2005- yilning 2- yanvar kuni 30 000 so'm pul qo'ydi. Agar         jamg'arma banki yiliga jamg'armaning 30%i miqdorida daromad bersa, omonatchining puli         2008- yilning 2- yanvariga borib qancha bo'ladi?

439. Tomoni 4 sm bo'lgan kvadrat berilgan. Uning tomonlarining o'rtachalari ikkinchi kvadratning         uchlari bo'ladi. Ikkinchi kvadrat tomonlarining o'rtalari uchinchi kvadratning uchlari bo'ladi va         hokazo. Shu kvadratlar yuzlarining ketmaketligi geometrik progressiya tashkil qilishini         isbotlang. Yettinchi kvadratning yuzini toping.

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