log10 0.01 = ?
A
2
B
- 2
C
- 1/2
D
0.02
উত্তরের বিবরণ
প্রশ্ন: log10 0.01 = ?
সমাধান:
log10 0.01
= log10(1/100)
= log10(1/102)
= log10(10- 2)
= - 2 log1010
= (- 2) × 1 [ log1010 =1 ]
= - 2
0
Updated: 1 month ago
যদি logx2 = a এবং logx3 = b হয়, তাহলে logx72 = কত?
Created: 1 week ago
A
a + 2b
B
2a - 3b
C
a + 3b
D
3a + 2b
সমাধান:
দেওয়া আছে, logx2 = a এবং logx3 = b
logx72
= logx(8 × 9)
= logx(23 × 32)
= logx(23) + logx(32) [log(mn) = logm + logn]
= 3logx2 + 2logx3
= 3a + 2b [মান বসিয়ে]
0
Updated: 1 week ago
log5(x - 4) + log53 = log5(x + 2) - 1 হলে, x এর মান কত?
Created: 1 week ago
A
15
B
28/7
C
35/8
D
31/7
প্রশ্ন: log5(x - 4) + log53 = log5(x + 2) - 1 হলে, x এর মান কত?
সমাধান:
log5(x - 4) + log53 = log5(x + 2) - 1
⇒ log5{(x - 4) × 3} = log5(x + 2) - log55 [logaM + logaN = loga(MN) এবং logaa = 1]
⇒ log5(3x - 12) = log5{(x + 2)/5} [logaM - logaN = loga(M/N)]
⇒ 3x - 12 = (x + 2)/5
⇒ 5(3x - 12) = x + 2
⇒ 15x - 60 = x + 2
⇒ 15x - x = 2 + 60
⇒ 14x = 62
⇒ x = 62/14
∴ x = 31/7
0
Updated: 1 week ago
