Question

dla jakiej liczy x spelniony jest warunek a)2^x*4^2=8^2x (osiem do 2...?) "...?=x" b)(9^x)^2=3*9*3^x

Answer 1

 

Answer 2

a)

2^x *4^2 = 8^2x

2^x *(2^2)^2 = (2^3)^2x

2^x * 2^4 = 2^6x  /:2^4

2^x = 2^6x/2^4

2^x = 2^(6x-4)

6x-4 = x

6x-x = 4

5x = 4

x = 4/5

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b)

(9^x)^2 = 3*9*3^x

(3^2x)^2 = 3*3^2 *3^x

3^4x = 3^3 *3^x

3^4x = 3^(x+3)

4x = x+3

4x-x = 3

3x = 3  /:3

x = 1

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