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8^5 = 2^2m+3


Solve m

1 Answer

1 vote

Answer:


m=6

Explanation:

Exponent properties:

We can use exponent property
a^(b^c)=a^((b\cdot c)) to solve this problem.

Rewrite
8 as
2^3, then apply exponent property
a^(b^c)=a^((b\cdot c)) to simplify:


2^(3^5)=2^(2m+3),\\2^(15)=2^(2m+3)

If
a^b=a^c, then
b=c, because of log property
\log a^b=b\log a. Using this log property, you can take the log of both sides and divide by
\log a to get
b=c

Therefore, we have:


15=2m+3

Subtract 3 from both sides:


12=2m

Divide both sides by 6:


m=(12)/(2)=\boxed{6}

Alternative:

Given
8^5=2^(2m+3), to move the exponent down, we'll use log properties.

Start by simplifying:


\log 32,768=2^(2m+3)

Take the log of both sides, then use log property
\log a^b=b\log a to move the exponent down:


\log(32,768)=\log 2^(2m+3),\\\log (32,768)=(2m+3)\log 2

Divide both sides by
\log2:


2m+3=(\log (32,768))/(\log(2))

Subtract 3 from both sides:


2m=(\log (32,768))/(\log(2))-3

Divide both sides by 2:


m=(\log (32,768))/(2\log(2))-(3)/(2)=\boxed{6}

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