Find X, If : Logx 625 = -4

Find x, if : log_x 625 = - 4

Sum

log_x 625 = - 4

⇒ 625 = x^{- 4} ...[ Removing logarithm ]

⇒ 5⁴ = `( 1/x )^4`
⇒ 5 = `1/x` ....[ Powers are same, bases are equal ]
⇒ x = `1/5`

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Chapter 8: Logarithms - Exercise 8 (D) [Page 111]

Chapter 8 Logarithms
Exercise 8 (D) | Q 9.1 | Page 111

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