Aylanish figuralari

AB = 2AD = 2

demak, konus sirti S_k = 9π.
Bundan, = .
Javob: .


14 – masala. Silindrning yasovchisiga tik bo`lgan kesimning yuzi Q ga, o`q kesimining yuzi esa S ga teng. Bu silindrning to`la sirtini va hajmini toping.
Y

echilishi:
Masala shartiga ko`ra, S<sub>ABCD</sub>= S, S<sub>asos</sub> = Q
Bundan quyidagi tengliklarni yozish mumkin:
S = AB · AD = 2AO · AD,
Q = π · AO<sup>2</sup>.
Bizga ma`lumki, silindr to`la sirti
S<sub>t.c.</sub> = S<sub>yon</sub> +2S<sub>asos</sub> . Yuqori dagi tengliklardan
AO= , AD = S/2 .
Bulardan,
S<sub>t.c</sub> = 2π · AO · AD + 2π · AO<sup>2</sup> = πS + 2Q.
Ma`lumki silindr hajmi V = π · AO² · AD ekanligidan,
V = S_t.c = πS + 2Q.
Javob: V == .
15 – masala. Konus yon sirtining yuzi asosining yuzidan ikki marta katta. Uning o`q kesimining yuzi Q ga teng. Konusning hajmini toping.
Yechilishi:
Masala shartiga ko`ra S_yon = 2 · S_asoc ,

\

S_ABC = Q. Ma`lumki S<sub>yon</sub> = πrℓ= π · AO · AC,
S<sub>asoc</sub> = πr<sup>2</sup> = π · AO<sup>2</sup>, S<sub>ABC</sub> = AO · OC.
formulalar yordamida hisoblanadi. Yuqo-
ridagilarni e`tiborga olsak, ℓ= 2r ya`ni
AC = 2AO, shu bilan birga
Q = AO · = AO² · .
ekanligini topish mumkin. Bundan AO =
Konus hajmi V = π · · · = .

Adabiyot:

1. Hakimov A.
2. Xolikov Q.S
3. Ungarov B.X.
4. Abjalilov S.X.
5. www.ziyonet.uz
6. www.NUR.uz