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0.5 log3 x=2 x = what

0.5 log3 x=2 x = what-example-1
User Kebs
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2 Answers

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Here is another method:

0.5 log_3 (x) = 2

Multiply both sides by 10 to get rid of the decimal:

10 * 0.5 log_3 (x) = 10 * 2

5 log_3 (x) = 20

Divide 5 out

(5 log_3 x)/(5) = (20)/(5)

log_3 x = 4

Now use the log rule
a = log_b b^a

4 = log_3 (3^4) = log_3 (81)

Since we have the same base

log_3 (x) = log_3 (81)
x = 81


User Big Dogg
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0.5\log_3x=2


Domain:x\in\mathbb{R^+}


0.5\log_3x=2\ \ \ |\cdot2\\\\\log_3x=4


Use\ the\ de finition\ of\ the\ logarithm:\\\\\log_ab=c\iff a^c=b


Therefore\ we\ have:\\\\\log_3x=4\iff3^4=x\to x=81

Answer: C. 81.
User Sola Yang
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