Question

Mohon untuk membantu menjawab soal ini kakak karena satu kebaikan seribu pahala.
no.2 dan 3
#dengan caranya!

Answer 1

Pembahasan:
Nomor 2.

5^(-2) = 1/(5^2) = 1/25
7^(-2) = 1/(7^2) = 1/49
5^(-1) = 1/(5^1) = 1/5
7^(-1) = 1/(7^1) = 1/7
sehingga
5^(-2) - 7^(-2) = (1/25) - (1/49) = (49-25)/(25×49)
= 24/(25×49)
dan
5^(-1) - 7^(-1) = 1/5 - 1/7 = (7-5)/(5×7) = 2/(5×7)
Jadi,
[5^(-2) - 7^(-2)]/[5^(-1) - 7^(-1)]
= [24/(25×49)] / [ 2/(5×7)]
= [24/(25×49)] × [ (5×7)/2]
= (24/2) × (5×7)/(25×49)
= 12 × (5/25) × (7/49)
= 12 × (1/5) × (1/7)
= 12/35

Pembahasan:
Nomor 3.

a. V = (1/3)πr²t
jika d = 2r atau r = 0,5d
maka
V = (1/3)π(0,5d)²t
V = (1/3) π(0,5)²d²t
V = (1/3) π(0,25)d²t
V = (1/3) π(1/4)d²t
V = (1/3)(1/4))πd²t
V = 1/12πd²t

b. V = (1/3)πr²t
3V = πr²t
πr²t = 3V
t = 3V / ( πr²) atau t = 3V ÷ (πr²)

c. V = 1/12πd²t
12V = πd²t
πd²t = 12V
d² = 12V /(πt)
d = √[12V /(πt)] atau d = √[(12V ÷ (πt)]

d. V = 1/12πd²t
12V = πd²t
πd²t = 12V
t = 12V / (πd²) atau t = 12V ÷ (πd²)




Selamat belajar
@ Wello1
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