document.write( "Question 127474: What is the value of logbase2 (1/sqrt32? \n" ); document.write( "
Algebra.Com's Answer #93397 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Set up the equation:
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\n" ); document.write( "\"y+=+log%282%2C%281%2F%28sqrt%2832%29%29%29%29\"
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\n" ); document.write( "Convert \"1%2Fsqrt%2832%29\" to a number by using a calculator to divide the square root of 32
\n" ); document.write( "into 1. The answer to this division is 0.176776695. Substitute this into the equation
\n" ); document.write( "to get:
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\n" ); document.write( "\"y+=+log%282%2C0.176776695%29\"
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\n" ); document.write( "Get this into a little more conventional form by transposing (or switching) sides to get:
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\n" ); document.write( "\"+log%282%2C0.176776695%29+=+y\"
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\n" ); document.write( "Now convert this logarithmic form to its equivalent form by raising the base of the logarithm
\n" ); document.write( "(the base being 2) to the y power and setting this equal to 0.176776695. In other words
\n" ); document.write( "you are converting the above logarithmic equation to the form:
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\n" ); document.write( "\"2%5Ey+=+0.176776695\"
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\n" ); document.write( "Then take the logarithm of both sides ... only this time let's use base 10 as the logarithm
\n" ); document.write( "because we can work in base 10 on a calculator. When you take the logarithm base 10 of both
\n" ); document.write( "sides the equation becomes:
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\n" ); document.write( "\"log%2810%2C2%5Ey%29+=+log%2810%2C0.176776695%29\"
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\n" ); document.write( "On the left side of this equation, use the exponent rule of logarithms to bring out the
\n" ); document.write( "exponent y as a multiplier of the logarithm. This results in the equation becoming:
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\n" ); document.write( "\"y%2Alog%2810%2C2%29+=+log%2810%2C0.176776695%29\"
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\n" ); document.write( "Now use your calculator to find that \"log%2810%2C0.176776695%29+=+-0.752574989\" and also
\n" ); document.write( "to find that \"log%2810%2C2%29+=+0.301029995\".
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\n" ); document.write( "Substitute these numbers into the equation in place of their logarithm forms and you have:
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\n" ); document.write( "\"y%2A0.301029995+=+-0.752574989\"
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\n" ); document.write( "Solve for y by dividing both sides of this equation by 0.301029995 and the result is:
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\n" ); document.write( "\"y+=+-0.752574989%2F0.301029995+=+-2.5\"
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\n" ); document.write( "And recall way back at the start of this exercise we said that y was equal to \"log%282%2C%281%2Fsqrt%2832%29%29%29\".
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\n" ); document.write( "So we can now say that \"log%282%2C%281%2Fsqrt%2832%29%29%29=+-2.5\"
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\n" ); document.write( "and the answer to this problem is -2.5
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\n" ); document.write( "Hope this helps you to understand the problem and one way of doing it. The process that
\n" ); document.write( "was used above to solve the problem essentially was the same process you use to develop the
\n" ); document.write( "change of base formula that you might be familiar with.
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