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4 votes
What is the solution to 2 In x = 4 In 2?
x =
DONE

User Bensal
by
3.1k points

2 Answers

2 votes

Answer:

4

Explanation:

Use the property of logarithms
n\ln x = \ln x^n. (The number in front of ln becomes an exponent--or vice versa!)

Using that property on both sides, you get


ln(x^2) = ln(2^4)

But that means


x^2=4^2\\x^2=16\\x=4

Notice that
x=-4 is not a solution because
\ln(-4) is undefined. Negative numbers do not have logarithms. The domain of
\ln x is the set of positive numbers.

User Jeorge
by
3.2k points
3 votes

Answer:

x =4

Explanation:

2 ln x = 4 ln 2

Divide each side by 2

2/2 In x = 4/2 In 2

ln x = 2 ln 2

Remember that a ln b = ln b^a

ln x = ln 2^2

ln x = ln 4

We are taking the natural log on both sides so , what we are taking the natural log of must be the same

x =4

User Davidkovsky
by
3.5k points