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Is there an error in the work and is the answer extraneous? if so why?​

Is there an error in the work and is the answer extraneous? if so why?​-example-1
User Jake Berger
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1 Answer

22 votes
22 votes

Answer:

x = 4

Explanation:

log₃[1 + log₃(2ˣ - 7)] = 1

log₃[1 + log₃(2ˣ - 7)] = log₃(3)

1 + log₃(2ˣ - 7) = 3

log₃(2ˣ - 7) = 2

log₃(2ˣ - 7) = log₃(3)²

2ˣ - 7 = 9

2ˣ = 9 + 7

2ˣ = 16

2ˣ = 2⁴

x = 4

By putting x = 4 in the original equation,

log₃[1 + log₃(2⁴ - 7)] = 1

log₃[1 + log₃(16 - 7)] = 1

log₃[1 + log₃(9)] = 1

log₃[1 + log₃(3)²] = 1

log₃[1 + 2] = 1

log₃[3] = 1

1 = 1

Therefore, x = 4 is not the extraneous solution and there is no error in your answer.

User Pmwood
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3.2k points