document.write( "Question 634579: Let f (x, y) = x2 + 2xy + 2y2 − 6y + 2. Find & identify all relative max’s and
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Algebra.Com's Answer #399766 by ewatrrr(24785)\"\" \"About 
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\n" ); document.write( "Hi, Previously Posted
\n" ); document.write( "f(x, y) = x^2 + 2xy + 2y^2 -6y + 2
\n" ); document.write( "∂ f/∂ x = 2x + 2y
\n" ); document.write( "∂ f/∂ y = 4y + 2x - 6
\n" ); document.write( " 2x + 2y = 0
\n" ); document.write( " 2x + 4y = 6
\n" ); document.write( " 2y = 6
\n" ); document.write( " y = 3 and x = -3
\n" ); document.write( "\"f%5Bxx%5D\" = 2
\n" ); document.write( "\"f%5Bxy%5D\" = 2
\n" ); document.write( "\"f%5Byy%5D\" = 4
\n" ); document.write( "D = \"2%2A4+-+2%5E2+=+4+%3E+0\"
\n" ); document.write( "f(x,y) has minimum at (-3,3)
\n" ); document.write( "f(-3, 3) = 9 -18 +18 -18 + 2 = - 7 \n" ); document.write( "
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