Find X, If : 42x = 1/32 - Mathematics

Find x, if : 4^2x = `1/32`

Sum

4^2x = `1/32`

⇒ ( 2 x 2 )^2x = `1/[ 2 xx 2 xx 2 xx 2 xx 2]`

⇒ ( 2² )^2x = `1/[ 2^5]`

⇒ 2^{2 x}^2x = 2^{- 5}

⇒ 2^4x= 2^{- 5}

We know that if bases are equal, the powers are equal
⇒ 4x = - 5
⇒ x = `(-5)/4`

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Solving Exponential Equations

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Chapter 7: Indices (Exponents) - Exercise 7 (B) [Page 100]

Chapter 7 Indices (Exponents)
Exercise 7 (B) | Q 2.1 | Page 100

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