document.write( "Question 894861: Dear Sir/Madam, \r
\n" ); document.write( "\n" ); document.write( "Please help me with this logarithm problem.\r
\n" ); document.write( "\n" ); document.write( "If log2a + logbb ≥ 6, then the least value of a + b is.\r
\n" ); document.write( "\n" ); document.write( "note: the bases are 2 and b\r
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\n" ); document.write( "\n" ); document.write( "Thank you very much!
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Algebra.Com's Answer #542383 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
logbb can be shown as log(b,b)
\n" ); document.write( "log2a can be shown as log(2,a)\r
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\n" ); document.write( "\n" ); document.write( "your equation is log(2,a) + log(b,b) >= 6\r
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\n" ); document.write( "\n" ); document.write( "since log(b,b) will always be equal to 1, then b can be any legitimate value greater than 0.\r
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\n" ); document.write( "\n" ); document.write( "since log(b,b) will always be equal to 1, your equation becomes:\r
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\n" ); document.write( "\n" ); document.write( "log(2,a) + 1 >= 6\r
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\n" ); document.write( "\n" ); document.write( "subtract 1 from both sides of this equation to get log(2,a) >= 5\r
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\n" ); document.write( "\n" ); document.write( "solve for log(2,a) = 5 to get log(2,a) = 5 if and only if 2^5 = a which occurs when a = 32.\r
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\n" ); document.write( "\n" ); document.write( "so log(2,32) = 5\r
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\n" ); document.write( "\n" ); document.write( "that appears to be the minimum value for a.
\n" ); document.write( "if a > 32, then log(2,a) will be greater than 5
\n" ); document.write( "if a < 32, then log(2,a) will be less than 5.\r
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\n" ); document.write( "\n" ); document.write( "for example:\r
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\n" ); document.write( "\n" ); document.write( "log(2,64) = 6 which is greater than 5.
\n" ); document.write( "log(2,16) = 4 which is less than 5.\r
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\n" ); document.write( "\n" ); document.write( "a has to be greater than or equal to 32 and b has to be greater than or equal to 0.
\n" ); document.write( "therefore, a + b has to be greater than or equal to 32.\r
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\n" ); document.write( "\n" ); document.write( "that's your solution as far as i can tell.\r
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