log102 + log10(b + 2) = log10(b - 1) + 1 হলে, b এর মান কত?
A
7/4
B
9/4
C
5/4
D
11/4
উত্তরের বিবরণ
সমাধান:
log102 + log10(b + 2) = log10(b - 1) + 1
⇒ log102 + log10(b + 2) = log10(b - 1) + log1010
⇒ log10{2(b + 2)} = log10{10(b - 1)}
⇒ 2(b + 2) = 10(b - 1)
⇒ 2b + 4 = 10b - 10
⇒ 4 + 10 = 10b - 2b
⇒ 14 = 8b
⇒ b = 14/8
∴ b = 7/4
0
Updated: 9 hours ago
2log105 + log1036 - log109 =?
Created: 2 weeks ago
A
2
B
100
C
37
D
4.6
2log105 + log1036 - log109 = log1052 + log1062- log1032 [ plogkM = logkMp]
= log10 {(52×62)/32} [logkM + logkN = logk(MN), logkM – logkN = logk(M/N)]= log10{(25 × 36)/9}= log10100= log10102= 2log1010= 2.1= 2
= log10 {(52×62)/32} [logkM + logkN = logk(MN), logkM – logkN = logk(M/N)]
0
Updated: 2 weeks ago
যদি logx324 = 4 হয়, তবে x এর মান কত?
Created: 1 week ago
A
3√2
B
4√2
C
5√2
D
√2
প্রশ্ন: যদি logx324 = 4 হয়, তবে x এর মান কত?
সমাধান:
logx324 = 4
⇒ x4 = 324
⇒ x4 = 81 × 4
⇒ x4 = 34 × 22
⇒ x4 = 34 × (√2)4
⇒ x4 = (3√2)4
⇒ x = 3√2
∴ x = 3√2
0
Updated: 1 week ago
logx(1/32) = - 5 হলে x এর মান কত?
Created: 1 day ago
A
2
B
3
C
5
D
- 5
প্রশ্ন: logx(1/32) = - 5 হলে x এর মান কত?
সমাধান:
logx(1/32) = - 5
⇒ x- 5 = 1/32
⇒ x- 5 = 1/25
⇒ x- 5 = 2- 5
⇒ x = 2
0
Updated: 1 day ago
