document.write( "Question 4587: I need help with these two problems.
\n" ); document.write( "x^4 + 5x^3 + x^2 - 25 =0 and 3x^(3/2) + 7x^(1/3) = 6.
\n" ); document.write( "I tried to group the first one but got stuck. I have no idea how to do the second problem. Need help before Monday\r
\n" ); document.write( "\n" ); document.write( "Nicole' \n" ); document.write( "
Algebra.Com's Answer #2123 by khwang(438)\"\" \"About 
You can put this solution on YOUR website!
(i) x^4 + 5x^3 + x^2 - 25 =0
\n" ); document.write( " x^3(x + 5) + x^2 - 25 =0
\n" ); document.write( " x^3(x + 5) + (x+5)(x-5) =0
\n" ); document.write( " (x+5)(x^3 + x - 5) = 0
\n" ); document.write( " So, x = -5 or x^3 + x - 5= 0
\n" ); document.write( " However,unfortunately,it is impossible to factor out
\n" ); document.write( " x^3 + x - 5 =0 unless you use the Cartan's formula about the cubic
\n" ); document.write( " polynomial to find the roots.
\n" ); document.write( " If you go to quickmath.com you can get the complicated
\n" ); document.write( " solutions of 1 real and two conjugate complex numbers.
\n" ); document.write( " But I think it is beyond what your level of learning.
\n" ); document.write( " [Maybe you only need one root.]
\n" ); document.write( " \r
\n" ); document.write( "\n" ); document.write( " (ii) 3x^(3/2) + 7x^(1/3) - 6 = 0.
\n" ); document.write( " Let u = x^(1/3), we have
\n" ); document.write( " 3 u^2 + 7 u - 6 = 0.
\n" ); document.write( " Factor out: (3u + 2)(u -3) =0
\n" ); document.write( " So, u = -2/3 or 3.
\n" ); document.write( "
\n" ); document.write( " Hence, x^(1/3) = -2/3 , x = -(2/3)^3 = -8/27
\n" ); document.write( " or x^(1/3) = 3 , x = 27.
\n" ); document.write( " Plz check by yourself.\r
\n" ); document.write( "\n" ); document.write( " Kenny \n" ); document.write( "
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