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UP TGT Mathematics 2019 Official Paper

Option 1 : 2

CT 1: हिन्दी (आदिकाल)

6301

10 Questions
40 Marks
10 Mins

**Concept:**

log a^{b }= b × log a

log_{a}a = 1

**Calculation:**

logx 4 + logx 16 + logx 64 = 12

⇒ logx 4 + logx 4^{2} + logx 4^{3} = 12

⇒ logx 4 + 2 × logx 4 + 3 × logx 4 = 12

⇒ 6 × logx 4 = 12

⇒ logx 4 = 2

⇒ logx2^{2} = 2

⇒ 2 log_{x} 2 = 2

⇒ logx 2 = 1

⇒ logx 2 = log_{2}2

On comparing, x = 2