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What value of x would make the expression below equal to 8? Photo provided! 20points!

What value of x would make the expression below equal to 8? Photo provided! 20points-example-1

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For this case, we must find the value of "x" so that the given expression is equal to 8.

That is to say:


(\sqrt [5] {8 ^ 3}) ^ x = 8

We apply "ln" to both sides of the equation to remove the exponent variable:


ln ((\sqrt [5] {8 ^ 3}) ^ x) = ln (8)\\xln (\sqrt [5] {8 ^ 3}) = ln (8)\\xln (\sqrt [5] {512}) = ln (8)

We rewrite 512 as:


512 = 32 * 16 = 2 ^ 5 * 16\\xln (\sqrt [5] {2 ^ 5 * 16}) = ln (8)

By definition of power properties we have:


\sqrt [n] {a ^ m} = a ^ {\frac {m} {n}}

So:


xln (2 \sqrt [5] {16}) = ln (8)

We clear x:


x = \frac {ln (8)} {ln (2 \sqrt [5] {16})}

In decimal form,
x = 1.6 periodic number

ANswer:


x = \frac {ln (8)} {ln (2 \sqrt [5] {16})}\\x = 1.6\ periodic\ number

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