document.write( "Question 1009871: In the binomial expansion of (k+ax)4 the coefficient of x2 is 54.
\n" ); document.write( "Given that a and k are both positive, find the value of ak. \r
\n" ); document.write( "\n" ); document.write( "This is my working:
\n" ); document.write( "(k+ax)^4 = k^4 + 4k^3ax + 6k^2ax^2 + 4kax^3
\n" ); document.write( "=6k^2a = 54
\n" ); document.write( "=k^2a = 9
\n" ); document.write( "ka = 3\r
\n" ); document.write( "\n" ); document.write( "Given also that the coefficient of x in the expansion is 48, find the value of k
\n" ); document.write( "?? \n" ); document.write( "
Algebra.Com's Answer #625363 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
In the binomial expansion of (k+ax)4 the coefficient of x2 is 54.
\n" ); document.write( "Given that a and k are both positive, find the value of ak.
\n" ); document.write( "This is my working:
\n" ); document.write( "(k+ax)^4 = k^4 + 4k^3ax + 6k^2(ax)^2 + 4k(ax)^3 + (ax)^4
\n" ); document.write( "=6k^2a^2 = 54
\n" ); document.write( "(ka)^2 = 9
\n" ); document.write( "ka = 3
\n" ); document.write( "--------
\n" ); document.write( "Given also that the coefficient of x in the expansion is 48, find the value of k
\n" ); document.write( "4k^3a = 48
\n" ); document.write( "k^3a = 12
\n" ); document.write( "(ak) = 12/k^2
\n" ); document.write( "--------
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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